Editor: Fernand J. Weiland
Remanufacturing AutomotiveMechatronics & Electronics
Not a threat but an opportunity
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Table of Contents Foreword By the Editor ………………………………………………………………………………………..3 Preface By Prof. Rolf Steinhilper …………………………………………………………………………..5 Remanufacturing New and Future Automotive Technologies By Fernand J. Weiland…………………………………………………………………………...13 Selected and Applied Test and Diagnosis Methods for Remanufacturing Automotive Mechatronics and Electronics By Dr.-Ing. Stefan Freiberger……………………………………………………………………35 Sustainable Development by Reusing Used Automotive Electronics By Fernand J. Weiland ……………………………………………………………………….....83 Research of Internet & Scientific Databases on Reusing and Inspection of Used Electronics Fernand J. Weiland …...…………………………………………………………………………89 Remanufacturing of Mechatronic and Electronic Modules for Transportation Vehicles – Challenges and Opportunities By Rex Vandenberg……………..……………………………………………...............……….97 Remanufacturing Electronic Control Modules – Evolution in Progress By Joseph Kripli………………………………………………………………………………….111
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FOREWORD OF THE EDITOR
As the Chairman of the Automotive Parts Remanufacturers Association’s Electronics &
Mechatronics Division, it is my objective to ensure that our members enjoy the benefits of
their membership. Among the many services an association can provide such as lobbying,
facilitating networking opportunities, publishing newsletters and newspapers, etc., I
decided to focus my efforts on technical communications. My objective is not to educate
our members on existing products which they are already familiar with, but to inform them
about future product changes and encourage them to embrace new technologies.
As a new division, the Electronics & Mechatronics Division has enjoyed tremendous
industry support which has been reflected by the large attendance at our meetings. Since
our start in 2006, we have had many meetings, clinics and plant tours. I would like to give
special thanks to all those who have contributed their time and talent as board members,
as speakers, and plant owners. They all have significantly contributed to the success of
this division. To encourage all members of our association to embrace the new E & M
technologies, I decided to edit a small book with the aim of exploring the changes which
will happen to their product lines.
Many thanks go to my friends and true professionals, Joe Kripli from Flight Systems and
Rex Vandenberg from Injectronics, who have greatly contributed to this book and to our
clinics, it is always a joy to work with them. Special thanks and gratitude also go to Stefan
Freiberger, a young, brilliant engineer who has significantly contributed to this book as
both author and technical editor. My debt is also to my friend Rolf Steinhilper, who has
supported me with his advice throughout the creation of this book, and has shared my
enthusiasm for remanufacturing for the last 20 years.
Lastly, many thanks to all the participants to our clinics,
to Bill Gager, President of APRA and his staff, in
particular Global Connection editor Kirsten Kase, who
have helped me in getting my job done as the chairman
of our division and as the editor of this book.
Fernand J. Weiland Chairman APRA Electronics & Mechatronics Division
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5
Preface By Prof. Rolf Steinhilper
Three areas: 1. Service Engineering (a new scientific discipline discovered only recently),
2. Automotive Maintenance (a task undergoing radical changes because of the
introduction of electronics and mechatronics into cars) and 3. Remanufacturing
Technologies (also challenged by cars’ electronics and mechatronics) form the
background of this very interesting new book edited and composed by Fernand Weiland.
After outlining the key challenges, it presents new technologies and opportunities mainly in
the field of remanufacturing automotive electronics, profiting from the pioneering spirit and
the expertise of a handful of innovative personalities around the globe who are willing to
share their knowledge with those who are also taking part in this exciting journey.
So it is a real pleasure and honor for me to give some introductory remarks in a preface to
this book, which I hope to be the ignition for inspiring a sequence of more good news and
valuable information for the rapidly developing remanufacturing technology of automotive
electronics and mechatronics.
1. SERVICE ENGINEERING – A NEW SCIENTIFIC
DISCIPLINE
The term ‘Service Engineering’ has now been around for a little more than ten years,
describing a challenging and fascinating field of work besides the engineer’s classic
disciplines such as design engineering, manufacturing
engineering or industrial engineering.
Being a huge new field, Service Engineering is defined in the
academic world as the ‘systematic development and design of
services using appropriate models, methods and (software) tools’.
Given this definition, Service Engineering is positioned in-
between engineering and economic sciences. Thus it is driven by
both the transition from production-based to service-oriented
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economies as well as by the possibilities of new information and communication
technologies such as B-to-B and B-to-C activities via the internet.
Service Engineering – and in particular Technical Service Engineering for cars – aims at
developing processes for maintaining a car’s performance (and thus also its energy
consumption and emissions) on the levels it was designed for, as well as providing know-
how and spare parts to fix failures (and thus reach or even extend the product’s desired
lifetime) – it is therefore of real significant economic and ecologic relevance within the total
life cycle of a car.
So far, however, scientific research & development efforts towards innovative Technical
Service Engineering is still a widely ‘unexplored territory’ – but the potentials are both huge
and promising.
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2. AUTOMOTIVE AFTERMARKET SERVICES –
BUSINESS OF WORLD SCALE AND SCOPE
The so-called ‘automotive aftermarket’ – the business of car repairs and spare part
supplies – is of wide scope: both in volume and in secrecy (!).Regarding sales, the global
automotive aftermarket business is worth 600 billion Euros (850 billion US $) which means
only around one third of the size of the global automotive business. But as figure 1 shows,
that regarding profits, the automotive aftermarket contributes three times as much than
new car sales to the profits of the automotive business!
Figure 1: Automotive Service – How big is it?
0.3% Used car
warranty
12% Sale of used
cars
17% Sale of new
cars
17% Financing, insurance
13% Fuel, oil,
tyres
41%
Spare
parts, service
Originof profits in the automotive industry
� Global aftermarket worth over EUR 600 billion(= USD 888 bn = JPY 94,653 bn = CNY 6,315 bn)
� Aftermarket equals 1/3 of the global automotiveindustry turnover of EUR 1,889 billion
� Continued growth over the coming years
� Aftermarket makes up more than 50% of profits
Source:
Booz Allen Hamilton from Automobilwoche no.12 (2005) and OICA (2007)
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The majority of the automotive service and spare parts business, to some extent
depending on the geographical region it is operating in, is done by the so called ‘IAM’
(Independent Aftermarket), not primarily by the ‘OEM/OES’ (Original Equipment
Manufacturer/Supplier), see figure 2.
Figure 2: Independent Aftermarket (IAM) vs. Original Equipment Services (OES).
This competition between OEM/OES and IAM is tough, but it is of course good news for
both technological progress and service innovations for the customers/car owners.
3. TECHNOLOGICAL TURNAROUNDS OF AUTOMOTIVE
MAINTENANCE AND REMANUFACTURING
TECHNOLOGIES
The rapid introduction of computer controls, which operate engine and power train
management, assist driving, steering, braking, suspension and many other safety,
transmission and/or comfort functions in today’s vehicles, is challenging both service
operations and skills along the car’s life cycle as well as remanufacturing technologies and
54%
81% 82%
59%
80%66%
0%
20%
40%
60%
80%
100%
Original Equipment Services (OES)
Independent Aftermarket (IAM)
Market shares of Independent Aftermarket (IAM) and
Original Equipment Services (OES) in 2005
Source: GEP (2005)
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the involved failure diagnosis requirements. Figure 3 depicts the radical shift (or
technological turnaround) of automotive maintenance operations.
Figure 3: Automotive Service Engineering – New Technologies and Opportunities.
Many, if not most of these changes in automotive maintenance are caused by the
introduction of microcontrollers, electronic and mechatronic components for more and
more car functions.
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The remanufacturing technologies for such electronic and mechatronic components in
today’s and tomorrow’s cars also need to be improved and will see some significant
changes and extensions in the near future. These developments are the focus of all
following chapters of this book – so no details will be pointed out in this preface.
It should be stated, however, that many recent Research and Development projects which
are run together with OEMs/OESs and the IAM at the Chair Manufacturing and
Remanufacturing Technology at the University of Bayreuth, Germany, where Prof. Dr.-Ing.
Rolf Steinhilper and his team of 10 engineers also operate a European Remanufacturing
Technology Center, deal with the development of new remanufacturing technologies and
business opportunities for automotive electronics and mechatronics. The contents and
results of all these projects are clearly showing that in the intersection between up-to-date
know-how from the three areas Service Engineering, Automotive Maintenance and
Remanufacturing Technologies, many new opportunities arise, see figure 4.
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Figure 4: Automotive Maintenance Operations.
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4. ENJOY READING!
Already today most world class companies have remanufacturing operations to boost their
own productivity and competitiveness in the service sector. But remanufacturing is also a
business for the small, family-owned, local companies, which are the backbone of every
national economy. Small innovative remanufacturers often tie the most intelligent knots in
the global players’ networks.
Remanufacturing is an eco-innovation driver, with potentials on the economic and the
environmental sides as well. It will conquer new disciplines and new product areas like the
car electronics and mechatronics and open new markets.
We must also remember that the strongest driving force in our market place is always the
consumer – ‘technological push’ needs ‘marked pull’. Remanufacturing technology
matters, but not as much as the people who will buy the remanufactured components and
ultimately benefit. Fortunately, consumer research also indicates a rising awareness which
is more than just lip service towards protecting the planet; particularly if customers can
have some fun and save money at the same time. Remanufacturing offers this magic twin
opportunity.
So I am very grateful to my friend Fernand Weiland for publishing this book – but not only
my thanks go to him but all the other authors for undertaking this effort.
My best wishes mainly go to the readers of this book for their interest in the further
advancement of the great concept of remanufacturing. There is a strong potential for
growth – the kind of healthy, balanced growth we need.
Remanufacturers are in business at the right time in the history of the world to provide
answers to many of our economic, environmental and employment challenges. Enjoy
reading, grasp the opportunities in the areas of vehicle electronics and mechatronics and
take action!
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REMANUFACTURING NEW AND FUTURE AUTOMOTIVE TECHNOLOGIES
By Fernand J. Weiland, FJW Consulting, Cologne Germany)
1. A NEW DEFINITION FOR REMANUFACTURING
AUTOMOTIVE ELECTRONICS AND MECHATRONICS
Until the advent of mechatronics and electronics controllers, the definition for automotive
remanufacturing was clear:
A remanufactured automotive component is the functional equivalent of a new component
and according to the Automotive Parts Remanufacturers Association (APRA)
Recommended Trade Practice the exact definition was, “Remanufacturing means
renovating used vehicle parts or components in accordance with the generally accepted
state of the art so that they can perform their function similar to new ones.
Remanufacturing regularly consists of dismantling the used units into their components,
checking these components, repairing defective components or replacing them with new,
reassembling the units, readjusting as necessary and submitting them to a final test.” The
unit will be reassembled in such a manner that it is returned to its original status and
performs like new.
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Figure 1: Remanufacturing process steps.
This definition, created for “traditional remanufacturing,” in the future will also apply to
mechatronics, however, for electronic controllers the definition will have to be adapted.
Electronic controllers, also called electronic control modules/units (sometimes colloquially
called black boxes), are computers equipped with passive and active electrical/electronics
components. They do not have mechanical components and therefore the need to
completely disassemble the entire unit is not necessary. When an electronic unit needs to
be opened, the cleaning will normally be light, since the units are hermetically sealed.
Defective components will need to be changed with new, and some critical components
may also be changed out completely for safety or reliability reasons. In this context it is
interesting to note whether electronic control units which have already been used and
continue to work properly can be reused again without any intervention. The German
Fraunhofer Institute IZM has studied this criteria and an interim report is available in this
book.
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2. “REMANUFACTURED PARTS” ARE THE BEST
CHOICE
Figure 2: Remanufactured Parts.
To service and repair motor vehicles with “used parts” or “repaired parts” is not the best
choice. Used parts have not been corrected for any potential problems. They have a
limited life expectancy. Not only will it not be an economical choice to use these parts, but
most importantly it can be an unsafe replacement. Furthermore, used parts procured from
car dismantlers are generally not easily available. “Repaired parts” have not been fully
disassembled, inspected or rectified -- their full function is not certain – however, they are
an environmentally friendly alternative, but not without risks to the buyer. “New parts” are
not the best economic choice either, because they are more expensive then
remanufactured units and they are surely not an environmentally friendly alternative.
“Remanufactured parts” are simply not only the best choice and the best buy, but
environmentally the only viable alternative. Remanufacturing saves material and energy
and the parts are (re)manufactured to high quality standards. In comparison to
manufacturing new units, remanufacturing uses 90% less material and 90% less energy!
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Figure 3: Vehicles in Europe and USA.
3. GLOBAL POTENTIAL SALES FOR AUTOMOTIVE
REMANUFACTURED PRODUCTS (AND
MECHATRONICS)
Globally speaking, the biggest market for remanufactured products is North America.
Europe is number two and the rest of the world is only an emerging market. In the United
States remanufacturing has been in place since 1940 and has steadily developed over the
years. Today the market is mature and remanufactured products have established a
dominant position against new, used or repaired units. In Europe remanufacturing has not
reached the same level, though the introduction in the United Kingdom dates back as early
as 1945 and in Germany, 1947. The main reasons for this slower growth have been that
Europe has been a market where garages tended to repair rather than use
remanufactured units. However, in recent years this trend has changed and the popularity
of remanufacturing is now progressing well.
The question for America and Europe is how will the new technologies of mechatronics
and electronics influence remanufacturing? Will the higher technological barriers hinder
the development of remanufacturing? At this juncture no one can reliably predict which
position remanufacturing will hold in 15-20 years. But encouraging all remanufacturers to
embrace the change now will not only mean challenges but also opportunities. As an
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association APRA has decided to facilitate education and networking in support of these
technological developments.
Figure 4: European annual production of remanufactured units.
4. EUROPEAN FUTURE POTENTIAL FOR
REMANUFACTURING
In terms of communicating volumes or number of units remanufactured every year, there
are very few reliable sources. APRA is one of the only sources available, and quotes for
North America a market of 60 million units each year and for Europe 20 million. If one
considers that the number of vehicles in use in the United States is around 200 million and
in Europe approx. the same number, one can asses that the potential in Europe leaves
room for growth. However, an accurate estimation of further growth is difficult because too
many factors will influence the development.
The positive short/medium term growth will certainly come from products like air
conditioning compressors, automatic transmissions, etc. These product lines will
increasingly equip more and more European cars and a new potential for remanufacturing
will emerge. A further area of growth is expected to come from components for heavy duty
vehicles. Potential growth is also expected in the areas of Eastern and Southern Europe
where remanufacturing is not yet as highly developed as in other parts of Europe. APRA
estimates that by the year 2015 the total European volume will reach 30 million units.
Compared to the year 2000 this is two times more! Beyond this date it is difficult to predict
the future of remanufacturing due to the potential impacts of mechatronics and electronics.
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Figure 5: Potential units to be remanufactured.
5. “TRADITIONAL” REMANUFACTURED PRODUCTS
The list of parts which have traditionally been remanufactured, also called “hard parts,” is
long (see table above). Most are mechanical and hydraulic parts, however, electrical parts
like electrical starter motors and electrical generators represent a significant part of
“traditional” remanufacturing. They all have been fitted to our vehicles for many years and
over time they have only slightly changed in technology. Remanufacturers have always
been able to cope with technical changes. By nature remanufactures are very inventive
and creative and when original technical specifications for products are not available for
remanufacturing, they perform reverse engineering, a great capability which
remanufacturers have. Over the years remanufacturers have invested in very
sophisticated tools, not only for the remanufacturing process, but also for the extremely
important work of testing the final quality of their products. All of these capabilities will help
them when they face the important change from traditional components to mechatronics
and electronics.
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Figure 6: Remanufacturing product life cycle.
6. THE REMANUFACTURING PRODUCT/TECHNOLOGY
LIFE CYCLE
In remanufacturing every product line/technology will follow a life cycle, from “new/future
products,” to “current products,” to “mature products,” and finally to “phasing out products.”
With products maturing, the remanufacturing volume will increase and so will productivity
and profits. At the end of the cycle they will phase out, and at that time the volume and
prices will decline and the product will become a niche product. Electrical power steering,
for example, are “new/future products” which will definitely increase in volume over time
and follow the above outlined cycle. But at the same time the traditional hydraulic power
steering, which is a mature product, will decrease in volume and finally will phase out and
be replaced by these new electrical power steerings. Most of the time phasing out is due to
changing technology. Volume reduction can also be caused by increased original product
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reliability, causing the volume required for servicing/repairing cars to decline. The
profitability of reman components will vary significantly during their life cycle. At the start,
when up-front investments and learning cost are high, profitability will be low, but with
higher volumes, due to economies of scale, the margins earned will reach the highest
value. Future mechatronics remanufacturing will follow this path and when it reaches the
volume production phase the earnings will be very attractive.
Figure 7: Evolution of vehicles in use. Over a period of ca. 15 years the conventional hydraulic power
steering will gradually be replaced by the electrical assisted power steering (EAS).
7. HYDRAULIC POWER STEERING VERSUS
MECHATRONICS POWER STEERING
A typical example to demonstrate the changes of a component during the life cycle is the
power steering fitted to the Volkswagen Golf cars. Until 2005 this model was fitted with
traditional hydraulic power steering, but starting in 2005 Volkswagen decided to install a
completely new technology: the electrically driven and electronically controlled power
steering. This is a typical example of a “traditional” component which was converted to a
mechatronic unit. The number of cars in use, which still have hydraulic power steering, is
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very significant and it will take up to 10-15 years until all Golf in use are equipped with the
new mechatronic version. Despite this, remanufacturers must embrace the new
technology now if they wish to stay in this business. Volkswagen is not the only OEM
changing to mechatronics power steering. Fiat, Opel and others have changed to the new
technology in 1998 and the aftermarket, i.e. remanufacturing business, for these units has
already started.
Figure 8: Mechatronics units.
8. WILL THE COMPLEXITY OF MECHATRONICS BE A
THREAT FOR REMANUFACTURING?
The list of automotive mechatronics components is as long as the list of “traditional”
components because any mechanical, electrical or hydraulic component will be replaced
by electronically controlled components, if it hasn’t happened already. The reasons for this
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are many since car components need to become more efficient in terms of energy
consumption, safer, smaller in size and weight and faster. The only way to improve all
these parameters is to control the units electronically and make them part of an
“interrelated car network.”
Furthermore, electronic control will also allow the customisation of car functions. By
changing the software instead of the hardware - which is much easier - an opportunity to
install and add additional features requested by the owner/driver of the car will be
presented to the technician. The downside of this will be the proliferation or increased
number of specific applications (part numbers) for each component and the question could
be asked if these changes or challenges are not too many or too big for the
remanufacturer to cope with. With the right determination and the right investment
remanufacturers can manage all this. In fact it will not be the first time the industry will be
dealing with such paradigm change, after all they have successfully managed the change
from mechanical carburetors to electronically controlled engine management systems,
which was quite a challenge
Figure 9: Bosch exchange program (source: Robert Bosch) Bosch is a very committed supplier of
remanufactured products which they call “Exchange”. Remanufactured Electronic Controlled Units
and Ignition Distributors are only two lines of many other product lines which they offer.
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9. WE ALL CAN LEARN FROM THE
REMANUFACTURERS OF ENGINE MANAGEMENT
SYSTEMS
Engine management systems (EMS) control the fuel injection, the ignition and the
emissions of combustion engines. In total the number of functions which they control is
approximately 100. The systems consist of many sensors and actuators and a computer or
Electronic Control Unit (ECU). These days nearly all cars are equipped with an EMS
system. When the change from carburetor to electronic injection happened 25 years ago,
some remanufacturers (Original or independent remanufacturers) did not hesitate to
embrace the change. They were not afraid to go through a difficult learning phase and they
were not reluctant to make the investments which such a new business required. In this
book you will be reading contributions made by two of these “pioneers.” The
remanufacturing processes which they invented were more on the electronic side and less
on the mechatronic side which were not yet developed. They now remanufacture all the
different types of controllers and the pertaining actuators which are the precursors of the
future mechatronic reman business. They are living evidence of what can be achieved by
remanufacturers who are determined to accept high challenges. They are the proof of
what remanufacturers often say, “In remanufacturing nothing is impossible!” My conclusion
is, “what has been done for electronics can also be done for mechatronics!”
Figure 10: TRW Electrically Assisted Steering (EAS) which is electrically column driven designed for
smaller vehicles (source: TRW Automotive).
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10. REMANUFACTURING MECHATRONICS IS A
FASCINATING PROCESS
What exactly is a mechatronic unit? It is the combination of a mechanical component with
an electrical actuator which is electronically controlled. The word mechatronics means a
combination of the words “mechanics” and “electronics.” Basically a mechatronic unit is
also a control system which, in automotive applications, is often a part of an entire vehicle
interconnected network. One of the first mechatronic automotive components which is
already finding its way into remanufacturing is electrical power steering! During driving,
power steering components are constantly actuated; therefore the need for service or
replacement often becomes necessary. This makes these components very attractive to
the remanufacturing business. The major Tier one manufacturers of these new
mechatronic components are ZF, Bosch, TRW, NSK and Koyo. These companies have all
designed different systems for different vehicles which have already been in production for
a number of years.
Figure 11: Elements of the TRW electrical column driven power steering: the electronic controller, the
angle sensor and the electrical motor actuator.
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11. ARE MECHATRONICS REALLY SO COMPLEX?
An Electrical Assisted Steering (EAS) system may look complex, but not so if we analyse it
component by component. The system can be divided into three major units:
1. The sensor which is part of the steering column that measures the angle the driver
makes in turning the steering wheel;
2. The Electronic Control Unit (ECU) which processes the sensor data information and
calculates and supplies the power,
3. The electrical motor which will rotate the column, that will drive the rack, and turn the
wheels of the car.
This automotive system is no different from many other control systems which we have
used for many years in all sorts of non automotive applications. In remanufacturing, the
three components of the EAS unit will be processed separately and each will be inspected,
repaired and tested. Repairing electrical motors is not new to remanufacturers and
rebuilding an ECU, as we have seen previously, is a process which remanufacturing
specialists are very capable of performing. After remanufacture and reassembly of all three
components into a complete unit, a final test will ensure the proper functioning of the unit.
This last check is one of the most important steps for the remanufacturer. Specialized
manufacturers of test equipment will provide the perfect piece of equipment required to do
this final job.
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Figure 12: Electronic control unit of an electrical power steering pump.
A micro controller of an electrical power steering pump and the frequency of potential
failures (defects) which need to be repaired during remanufacturing. Out of 100 units
which are returned for reman, only 10 units will have a defective microcontroller, 25
defective wiring or connectors and 40 units will show a problem with the power supply
modules.
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12. WHAT CAN GO WRONG IN AN ECU AND WHAT
NEEDS TO BE REMANUFACTURED
An ECU (electronic control unit) for a standard mechatronic unit like an EAS is significantly
less complex compared to an ECU for EMS. The number of parameters it controls or
computes is limited as are the number of electronic components. In total, the number of
passive and active components is modest. As a result the number of potential failures on
an ECU for an EAS is often limited to the more passive components like:
- connectors - for many reasons they are a weak point in any electronic unit;
- the wiring - mechanical stress and corrosion can cause a lot of problems, and
- the power supply - which consists of an often easy to diagnose and easy to replace
component.
The microcontroller itself is often the last source of complaint. Electronic semiconductors
(microchips, etc.) normally last “forever”. It is the electrical connections which are basically
mechanical connections that are often the problem makers!
Assuming the remanufacturer has the equipment and the data to test the unit, the
remanufacturing process of this ECU should not present them with a major problem.
Figure 13: TRW rear axle caliper is a combination of a hydraulic brake and an electrically driven parking
brake (source: TRW Automotive).
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13. AFTER EMS & EAS WHICH ARE THE NEXT
MECHATRONIC UNITS APPEARING IN
REMANUFACTURING?
After EMS (Engine Management Systems) and EAS (Electrical Assisted Steering) the next
interesting area we need to look at is braking. A mechatronic braking system which has
already existed for a number of years is ABS, a braking system which has mechatronic
components, like electrical solenoids and an electronic controller. Not many
remanufacturers are remanufacturing these components because the reliability and the
number of service incidents are so low that the volume for remanufacturing is not sufficient
to justify the investment to reman on a larger scale.
With the introduction of the combined hydraulic/electrical brake caliper (see figure16),
which is also a parking brake, remanufacturing mechatronics will enjoy a new business.
Calipers are components which are highly stressed and the frequent service and repair
that they require will make them an important mechatronic component for remanufacturing.
These electrical calipers have a hydraulic piston coupled with an electrical motor and a
gearbox. Not too complex for remanufacturing, but as for all mechatronics, an electronic
tester for inspecting and operating the calipers will be absolutely crucial. Fortunately such
testers exist already.
Figure 14: Side-mounted combined starter-generator with the electronic controller designed by Valeo
(source: Valeo Automotive).
29
There are many other areas where mechatronics will be applied, but let us look at a last
one which in traditional remanufacturing is one of the biggest reman volume providers, i.e.
electrical rotating machines or starter motors and generators. At this juncture it is difficult
to make an exact forecast of which of the existing new rotating machine concepts will be
fitted to volume cars.
I have chosen to discuss the Valeo design because it is the best example for illustrating
the direction these applications are moving. The Valeo design, which would fit in the
category of so called “micro hybrid power train,” is a side mounted combined starter-
generator. The mechanical/electrical concept is close to ‘traditional” rotating machines
except that it is electronically controlled. Other combined starter generators used for more
powerful applications, the so called “mild hybrid power trains,” are also controlled
electronically and the challenge to reman will not be very different than the Valeo machine.
The remanufacturing of these new machines will not be such a great problem; the bigger
hurdle will be, as for all mechatronics units, the electronic controller. For Starter-
Generators the controller will in addition be combined with an inverter for supplying the AC
current for the motor mode.
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14. HOW REMANUFACTURERS CAN HELP GARAGE
WORKSHOPS WITH BETTER DIAGNOSIS
The garage workshop is very familiar with remanufactured units which it has used
extensively for repairing cars over the last several decades. Remanufactured units offer an
attractive solution for returning defective cars to service. With the advent of electronics and
mechatronics, remanufacturing will positively expand in so far as the remanufacturer will
not only offer a product to the installer but also a technical service! The reason has to do
with the increased complexity of the units and the daily struggle of the garage technician
with the new technologies. Unfortunately for the garage, not only are the units more
complex but also the entire electrical car connections are now part of a multiplex network
called CAN bus.
Figure 15: On Board Diagnosis (source: Robert Bosch).
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Traditionally, the garage technician repairing cars had the capability to check the
components, but now with all components becoming mechatronics and interrelated, his
testing possibilities for individual components are very limited. One has to rely on what the
car testers will tell them about the status of the car systems, but often they will not tell him
the real status of the individual components. Only the remanufacturer has this true and
clear capability to inform the installer if a mechatronic unit is accurately working or not! As
a result, the remanufacturer can now help the garage to perform a better diagnosis, a
service which is new and will be very appreciated. Smart remanufacturers will offer this
competitive advantage and will be compensated with greater market shares!
Figure 16: Performance of electronic control units (source: Robert Bosch). Over the last 25 years the
performances of electronic controllers for EMS have increased by a factor of 100! In the
same time span, the size/volume of the controllers have decreased five times. This is
practically a specific performance improvement of a factor of 500!
32
15. MECHATRONIC COMPONENTS HAVE A MUCH
SHORTER DESIGN CYCLE
If we compare the changes in Engine Management Controllers over the last three
decades, we will see at least three significant paradigm changes (see figure 16). If in
comparison we look at “traditional” components like Brake callipers, Hydraulic power
steering, etc. we have, until the recent advent of mechatronics, not really seen one
significant paradigm change over a similar period. Brake callipers, power steering and
other components are only now going through a paradigm change, i.e. they will all become
mechatronic components.
To illustrate the current speed of change in the design cycle of electronics (and
consequently, mechatronics) the best examples are personal computers, mobile phones
and digital cameras. We replace these units every 3-5 years, some even more frequently.
Most of the time the reasons for this frequent changing technology is found in the
hardware and software. In automotive design we are seeing a similar evolution. For
example, for EMS (Engine Management Systems) the product design cycles have already
reached a stage of less than three years, according to a study made by the Technical
University of Dresden (Germany).
The bottom line of this evolution will be that design cycles for automotive components will
reduce considerably and OES aftermarket sales & service divisions will be highly
challenged to keep pace with these frequent changes. Fortunately remanufacturing can
easily cope with these challenges. In the past remanufacturers have always supplied the
aftermarket with products. It is not unusual that after more than 20 years after the OE
stopped production, remanufacturers are still capable of offering a reman unit for repairing
cars!
33
16. REMANUFACTURING IS A RELIABLE AND VERY
ATTRACTIVE SOLUTION FOR SHORT, MEDIUM & LONG
TERM SUPPLIES OF COMPONENTS FOR REPAIRING
VEHICLES
I do not have to reiterate the fact that remanufactured products are an attractive solution for
replacing defective components. I do however, wish to emphasize that for OEMs and Tier
Ones, the mechatronic components which are quickly becoming obsolete, will present an
immense challenge in terms of securing long term (15 years and more) supplies. For them,
remanufacturing will be the best choice and a very cost effective and safe alternative
compared to making new components. They will need to adopt the philosophy to offer
remanufactured units now and not at a later date. They need to create a system for the
return of defective units and they need to retain certain test equipment and data before they
dispose of them. Remanufacturing needs time to prepare, because it cannot happen
overnight when other alternatives, such as small batch production, redesign, produce an all
time batch, etc, have failed!
17. FINAL CONCLUSIONS
• “Active” car components will eventually become mechatronics components. The
conversion has already started and it will take a few years (2-5) until all new cars will
be equipped with them. It will take approximately 10 years until the majority of the cars
in use are equipped with them.
• Mechatronics will be a new area where remanufacturers can win a competitive edge if
they adopt the trend early enough.
• “Traditional” remanufacturers do not always have the know-how to tackle electronics
and mechatronics. They need to go through a learning process which will take time. I
recommend to subcontract or to work with the specialized electronics remanufactures
who can give valuable support.
• Investments of time, but also of money, are required to make the change. To create a
sound basis for the investment, remanufacturers must create a robust plan.
34
• In the future remanufacturing mechatronics will be an attractive program, not only to
offer to the independent aftermarket but also to offer to OEMs and Tier Ones, who
may decide to subcontract their programs.
• Mechatronics are high value products which will deliver higher margins and which will
not be easily copied by low labor countries. The parts proliferation will be such that
high volumes by part number will not be the norm.
• Remanufacturers should decide soon if they want to be in the mechatronic business.
Mechatronics needs high dedication; success will only come from embracing the new
technology with determination. Good luck!
35
Selected and Applied Test and Diagnosis Methods for Remanufacturing Automotive
Mechatronics and Electronics
By: Dr.-Ing. Stefan Freiberger; Bayreuth University
Structure:
1 Automotive Mechatronics
2. Test and Diagnosis in Remanufacturing
3. Test and Diagnosis of Mechatronics in Remanufacturing
4. Test and Diagnosis of Electronic Control Units in Remanufacturing
5. Test and Diagnosis of Actuators and Sensors in Remanufacturing
6. Remanufacturing of Electro Hydraulic Power Steering Pumps
7. Remanufacturing of Electronic Control Unit of an EHPS-Pump
8. Remanufacturing of Air Mass Sensors
9. Conclusion and Outlook
36
1 Automotive Mechatronics
1.1 Design of Mechatronic Systems
The task of mechatronic systems is the arranged and controlled conversion of electrical,
hydraulic, mechanical, thermal and pneumatic energy. Mechatronic systems are
characterized by at least one mechanical energy flow and one transfer of information. In
order to perform this task, the mechanical, electrical and electronic systems are closely
interconnected, exchanging data through a communication system. The following figure
shows the design of an integrated electronic system, to which literature increasingly refers
as mechatronic system.
Figure 1: Mechatronic systems.
Actuators and sensors represent the basis of the mechatronic system. Through analog or
digital signals, the electronic control units are able to communicate with the control system,
as well as with the sensors and the actuators. They are also built in the mechatronic system.
The properties of the system, e. g. dynamic characteristics, flexibility and learning aptitude
are mainly defined by the software in the electronic control unit.
1.2 Subassemblies within Mechatronic Systems
The following subsections give a closer insight to the actuators, sensors and electronic
control units, which represent the most important subassemblies of mechatronic systems
Mechatronic System
Basic System
Control System
Electronic control unit
Actuators Sensors
Desired values
Actual values Given values Energy,
Information,
Material
Energy,
Information,
Material
37
1.2.1 Actuator Subassembly
In many cases, automotive actuators comprised of an electronical input and a mechanical
output. The following actuators are frequently used in vehicles:
• Electronic actuators: e. g. direct current motors, electronical valves and generators.
• Fluid energetically actuators: e. g. valves, barrels and pumps.
With regard to their power-to-weight-ratio, the hydraulic actuators are clearly superior to the
electronical ones. The advantages of electronical actuators are inherent in their convenient
controllability, in their great dynamics, in their good degree of efficiency, the low costs of
production and the good testability. Due to the many advantages of the electronical
actuators, they are commonly used in vehicles, especially in those with medium requirement
of energy. Up to 100 electric motors are already installed in today’s luxury-class vehicles.
This trend is to be strengthened and spread towards every vehicle class. Especially
brushless dc motors will be installed in the future, since they posses a higher power density
combined with a good reliability. Hydraulic actuators are used for several rare applications
with a high requirement of energy, e. g. servo steering systems.
1.2.2 Sensor Subassembly
The task of sensors is to measure internal and external signals of a system, to convert these
signals and to send the signals to electronic control units. Most of, electrical signals are used
as sensor output. The value is transmitted by one of the following ways of signals.
• For amplitude analogue signals, the amplitude is proportional to the measurand.
• For frequency analogue signals, the frequency is proportional to the measurand.
• For digital signals, an encoded binary signal can be transformed into the measurand.
Furthermore, sensors can be classified according to their measuring principle. Table 1
shows the commonly used measuring principles in today’s vehicles.
38
Table 1: Measurands, measuring principles and applications in the vehicle.
Measurand Measuring principle (Code of the
measuring principle)
Measuring application (Code
of the measuring principle)
Acceleration Inductive (1), capacitive (2),
piezo-electric (3),
hall-effect (5)
Cross acceleration (2, 3, 5),
Lateral acceleration (2, 3, 5),
Crankshaft acceleration (3)
Revolution
speed
Inductive (1), hall-effect (5),
optical (6), magneto-resistive (10)
Gearbox rotation speed (1, 5),
Wheel rotation speed (1, 5, 10)
Pressure Capacitive (2), piezo-electric (3),
resistive (4), piezo-resistive (7)
Absorbing air pressure (7),
Charging air pressure (4, 7),
Breaking pressure (2, 4),
Flow rate Resistive (4), optoelectronic (8) Air flow (4),
Mass air flow (4)
Lenth,
Distance
Inductive (1), capacitive (2),
resistive (4), supersonic (12),
radar (11)
Accelerator value (1),
Seat adjustment stroke (4)
Clutch stroke (1),
Temperature Resistive (4), optoelectronic (8),
thermoelectrical (9)
Oil temperature(4),
Water temperature (4),
Exhaust gas temperature (4)
Vibration Piezo-electric (3) Knocking sensor (3)
Angle Inductive (1) capacitive (2), Resistive
(4),hall-effect (5), optoelectronic (8),
magneto-resistive (10)
Steering angle (8, 10, 5),
Damper angle (4),
Accelerator angle (1, 4, 5)
The table above shows some sensors that are used in vehicles. Due to the increasing
number of used sensors, the continuing trend is a miniaturisation of the systems - mainly in
order to economise weight and space.
1.2.3 Electronic Control Unit
With the introduction of the microcontroller more and more functions are being transferred to
electronic control units (ECUs). Modern cars may contain up to 100 ECU’s, mostly as part of
the complex mechatronic systems used in the power train, safety and comfort systems of
today’s vehicles. Optimal interaction between sensors, actuators, and the control units is a
basic requirement for the smooth functioning of the entire system. Unfortunately, in recent
years, the rising complexity has lead to a decrease in reliability and an increase in the
number of call-backs and breakdowns, especially for innovative vehicles. This, together with
the fact that the end-users’ costs for a single mechatronic system inside their cars range
39
between 200 and 3000 Euro, provides a strong incentive to remanufacture these
economically.
2 Test and Diagnosis in Remanufacturing
2.1 Remanufacturing Process Steps for Mechatronics
Especially with regard to systems that consist of networked subsystems - like mechatronic
systems, it makes sense to carry out an entrance test and diagnosis of the whole system,
before passing it on to the disassembly. This entrance test and diagnosis as a first step in
remanufacturing mechatronic systems gives information about the condition of the system.
The five common steps in remanufacturing can be added to the step of entrance test and
diagnosis of the system.
Figure 2: Process steps in Remanufacturing.
The entrance test and diagnosis divides the mechatronic systems into the fractions
remanufacturable and non-remanufacturable. During the second process step, the
4 5
1 Disassembly of the System 2
2 3
3 4
Reconditioning of Parts or Subsystems
5 Product Reassembly 6
Entrance Diagnosis of the System
Mechatronic
Systems
Remanufacturing
Process Steps
Test and Diagnosis of Subsystems
Quality Assurance
Final Test
Mechanic and
Electromechanic
Systems
1
Thorough Cleaning
40
disassembly, the two fractions are disassembled into different levels. Concerning the non-
remanufacturable systems, only the remanufacturable subassemblies (e. g. the sensors) or
parts (e. g. the casings) are disassembled, depending on the entrance test and diagnosis.
The non-remanufacturable parts are passed on towards material recycling or removal. The
remanufacturable systems run through a complete disassembly, a thorough cleaning to the
fourth process step of remanufacturing: the test and diagnosis of subsystems and parts. The
next step is the reconditioning of parts or subsystems and last but not least the product
reassembly and the final test. Having run through the different process steps mentioned
above, the remanufactured mechatronic systems can be delivered to the customer with their
original quality, their original effectiveness, original life-time, guarantee and service.
2.2 Boundary Conditions for Testing and Diagnosis in
Remanufacturing
Some of the remanufacturing companies work in cooperation with one or several original
equipment (OE) manufacturers. In the following, they will be referred to as OE manufacturer-
related remanufacturing companies. The main part of the remanufacturing companies
however is independent from original manufacturers and therefore these companies do not
cooperate with any OE manufacturer. Since the choice of the best methods for the test and
diagnosis of failures strongly depends on the cooperation with the OE manufacturers, the
two types of remanufacturing companies take different ways. Concerning the choice of test
and diagnosis methods, several basic requirements are stipulated for the two types of
remanufacturing companies:
Boundary conditions for OE manufacturer-related remanufacturing companies:
• Existence of drawings (control plans, port information, tolerances in geometry, form
and position).
• Existence of parts-lists (element designation, suppliers and assemblage Methods)
• Existence of specifications.
• If necessary: existence of original testing tools and test benches.
Boundary conditions for independent remanufacturing companies:
• No access to drawings.
• No access to parts lists.
• No information concerning specifications.
• No access to original testing tools and test benches.
41
2.3 Steps for the Test and Diagnosis in Remanufacturing
For the test and diagnosis of systems, subsystems and parts, the steps as presented in the
following figure are recommended.
Figure 3: Process steps for the test and diagnosis.
2.4 Methods for the Test and Diagnosis in Remanufacturing
There are a great number of different methods to test technical systems. Each method has
its special force and weakness. In account of technical or economical reasons, not every
known method can be applied in remanufacturing of mechatronic systems and their
subassemblies. The methods can either be divided into norm-based (deductive) and model-
based (inductive) methods or into signal based, signal model based and model based
methods.
Signal based methods are methods that use input, output and internal signals of the unit.
Signal model based methods are methods that use the stochastic coherences of signals or
the vibration behaviour of the signals. Model based methods use a mathematical model of
the system.
The symptoms are defined in such a way that deviations concerning the nominal or
reference state (specifications) indicate failures. In order to carry out an analysis of the
symptoms, every method has to be based on analytic and heuristic knowledge, concerning
the correlation of symptoms and failures. Only in this manner the failures, their nature,
reason, type, location and dimension can be safely diagnosed.
Choice of test and diagnosis methods
Generation of specification
Generation of test cases and input signals
Measurement under realistic conditions
Evaluation of the data
42
3 Test and Diagnosis of Mechatronics in
Remanufacturing
3.1 Potential Methods for Remanufacturing
The following figure shows potential methods for the test and diagnosis of mechatronic
systems in Remanufacturing.
Figure 4: Potential methods for the test and diagnosis of mechatronic systems.
3.2 Selection of Methods for Remanufacturing
Target of that chapter is to find out the best method or the best combination of methods for
the test and diagnosis of mechatronic systems in remanufacturing companies.
Remanufacturing companies are divided into independent (OE data are not available) and
OE manufacturer-related (OE data are available) companies.
3.2.1 For Independent Remanufacturing Companies (OE data are not
available)
The following table shows the result of an evaluation of the potential methods for the test
and failure detection of mechatronic systems for remanufacturing companies.
Potential test and diagnosis methods for mechatronic systems
Signal Based Methods
• Absolute Value
Control
• Characteristic
Curves
Signal Model Based
Methods
• Stochastic Signal
Model
• Spectral Analyze
Model Based Methods
• Parameter Estimation
• State Condition
• Parity Space
• Artificial Neuronal Networks
• Fuzzy Models
• Neuro Fuzzy Models
43
0 5 6 7 10
Table 2: Result of an evaluation for the test and diagnosis of mechatronic systems
(independent remanufacturing companies)
System knowledge
Efforts for model creation
Transferability
Possible ways of signalling
Failure test
Failure diagnosis
Invest
Duration of test and diagnosis
Efficiency share
Effort for model creation
Efficiency share
Technical effort
Efficiency share
Economical effort
Efficiency
Main Crit. Imp. in % 40 30 30
Single Crit. Imp. in % 37 23 40 35 45 20 55 45
Absolute Value
Control 8,3 8,5 9,2 1,9 5,2 2,0 7,7 5,2 8,7 3,4 6,6 6,5
Characteristic
Curves 8,3 7,9 8,1 8,2 8,9 5,7 6,3 6,6 8,1 8,0 6,4 7,6
Spectroscopic
Analysis 5,0 4,7 7,0 6,3 8,7 5,8 4,6 6,5 5,7 7,3 5,5 6,1
Stochastic Signal
Models 7,3 7,9 3,9 8,4 6,2 2,4 6,0 5,7 6,1 6,2 5,9 6,1
Fuzzy Models 5,0 4,1 6,3 8,8 8,7 4,7 6,0 5,5 5,3 7,9 5,8 6,2
Artificial Neuronal
Networks 8,5 4,7 4,1 10 8,8 6,0 3,2 6,6 5,9 8,7 4,7 6,4
Neuro Fuzzy Models 4,7 2,0 4,1 8,8 8,7 6,6 3,2 6,1 3,8 8,3 4,5 5,4
Parameter
Estimation 1,5 1,9 5,0 10 9,0 10 6,0 8,9 3,0 9,6 7,3 6,3
Parity Space 0,2 1,5 4,2 10 7,4 6,8 6,0 6,5 2,1 8,2 6,2 5,2
State Condition 1,9 2,1 5,0 10 7,4 5,2 6,0 6,5 3,2 7,9 6,2 5,5
The table above shows the summary of all calculated values, as well as the efficiency
shares and efficiencies of all potential methods for the test and diagnosis of mechatronic
systems in remanufacturing.
The following figure shows the recommended methods during the entrance and final test
and diagnosis in remanufacturing mechatronic systems.
44
Figure 5: Entrance and final test and diagnosis of mechatronic systems for independent remanufacturing
companies.
With expert knowledge, failure trees, results of FMEA analyses, failure data bases and
characteristics of the system in relation to the reference characteristics most of the failures
can be safely detected, localized and diagnosed. It is to note, that the method characteristic
curves can only detect those failures that influence the output signal.
Some failures, as for example cracks and deformations cannot be detected with the method
of characteristic curves. Therefore, a direct visual diagnosis is carried out before the
characteristic curves test, which is able to detect visible structural failures.
Entrance and final test and diagnosis of mechatronic systems: for independent remanufacturing companies
Direct Visual
Diagnosis
Specific
information
resources
• Knowledge of
the workers
• Specification
(e. g. pictures
of good units,
main failures,
FMEA results)
Gained
information
• Localized and
diagnosed
visual and
structural
failures, their
sources and
consequences
• Information
concerning the
sorting of the
systems for
further steps
Specific
information
resources
• Test and
diagnosis
hardware
• Specification
(e. g. input
signals, test
cases, set
output
signals)
Gained
information
• Localized and
diagnosed
failures
• Information
concerning
the sorting of
the systems
for further
steps
Characteristic
Curves
Systems with not diagnosed failures
Material flow
Systems with non-repairable failures
Systems with diagnosed failures
All systems
45
0 5 6 7 10
3.2.2 For OE Manufacturer-related Remanufacturing Companies (OE
data are available)
The following table shows the result of an evaluation of the potential methods for the test
and diagnosis of mechatronic systems for OE manufacturer-related remanufacturing
companies.
Table 3: Result of an evaluation for the test and diagnosis of mechatronic systems (OE
manufacturer-related remanufacturing companies)
Possible ways of
signalling
Failure test
Failure diagnosis
Invest
Duration of test
and diagnosis
Efficiency share
Technical effort
Efficiency share
Economical effort
Efficiency
Main Criteria Importance in % 50 50
Single Criteria Importance in % 35 45 20 55 45
Absolute Value Control 1,9 5,2 2,0 7,7 5,2 3,4 6,6 5,0
Characteristic Curves 9,0 8,9 5,7 6,3 6,6 8,3 6,4 7,4
Spectroscopic Analysis 6,3 8,7 5,8 4,6 6,5 7,3 5,5 6,4
Stochastic Signal Models 9,4 6,2 2,4 6,0 5,7 6,6 5,9 6,2
Fuzzy Models 8,8 8,7 4,7 6,0 5,5 7,9 5,8 6,9
Artificial Neuronal Networks 10 8,8 6,0 3,2 6,6 8,7 4,7 6,7
Neuro Fuzzy Models 8,8 8,7 6,6 3,2 6,1 8,3 4,5 6,4
Parameter Estimation 10 9,0 10 6,0 8,9 9,6 7,3 8,4
Parity Space 10 7,4 6,8 6,0 6,5 8,2 6,2 7,2
State Condition 10 7,4 5,2 6,0 6,5 7,9 6,2 7,0
The table above shows a summary of all calculated grades, as well as the efficiency shares
and efficiencies of all potential methods for the test and diagnosis of mechatronic systems.
The following figure shows the recommended methods during the entrance and final test
and diagnosis within the remanufacturing of mechatronic systems.
46
Figure 6: Entrance and final test and diagnosis of mechatronic systems for OE manufacturer-related
remanufacturing companies.
With regard to OE manufacturer-related and independent remanufacturing companies, the
entrance test and diagnosis as well as the final test and diagnosis are similar. The main
difference is that the OE manufacturer-related remanufacturing companies use the method
characteristic curves, while the independent remanufacturing companies use the method
parameter estimation.
Entrance and final test and diagnosis of mechatronic systems: for OE manufacturer-related remanufacturing companies
Specific
information
resources
• Knowledge of
the workers
• Specification
(e. g. pictures
of good units,
main failures,
FMEA results)
Gained
information
• Localized and
diagnosed
visual failures
and their
sources and
consequences
• Information
concerning
the sorting of
the systems
for further
steps
Specific
information
resources
• Test and
diagnosis
software
• Specification
(e. g. input
signals, test
cases, set
output signals,
transmission
behavior)
Gained
information
• Localized and
diagnosed
failures and
their sources
and
consequences
• Information
concerning
the sorting of
the systems
for further
steps
Systems with not diagnosed failures
Direct Visual
Diagnosis Parameter
Estimation
Material flow
Systems with non- repairable failures
Systems with diagnosed failures
All systems
47
4 Test and Diagnosis of Electronic Control Units in
Remanufacturing
4.1 Potential Methods for Remanufacturing
The following figure shows potential methods for the test and diagnosis of electronic control
units in remanufacturing.
Figure 7: Potential methods for the test and diagnosis of electronic control units.
The direct visual diagnosis can be used as an additional method. It is however not regarded
as an individual method, since it is not able to substitute the other ones. The reason for the
elimination of the stochastic signal methods is the extremely high amount of output signals
that would have to be evaluated for the failure detection. With regard to the model based
methods, only the function test and the artificial neuronal networks will be considered
further. In reference to the basic requirements, the methods fuzzy and neuro fuzzy models
are not economically feasible for electronic control units.
Potential methods for the test and diagnose of electronic control units
• Signal Based Methods
• Automatical Optic Diagnosis
• Bed of Nails Test
• Clip Test
• Flying Probe Test
• Manual Microscopic Diagnosis
• X- Ray Diagnosis
• Thermal Imaging
• Behavioural Test
Model Based Methods
• Function Test
• Artificial Neuronal Networks
48
Because of the main reasons mentioned below, the model based methods parameter
estimation, state extent estimation and parity space models will not either be considered:
• Not enough knowledge is known in the field of electronic control units in remanufacturing
companies.
• The effort to create a model of the unit is huge.
• These methods are only suitable for small electronic control units (controlling only up to
40 parts), which is not given in automotive electronics.
Instead of the model based methods parameter estimation, state estimation and parity
space, the functional test is potential for the test and diagnosis of electronic control units in
remanufacturing.
4.2 Selection of Methods for Remanufacturing
Target of that chapter is to find out the best method or the best combination of methods for
the test and diagnosis of electronic control units in remanufacturing companies.
Remanufacturing companies are divided into independent (OE data are not available) and
OE manufacturer-related (OE data are available) companies.
4.2.1 For Independent Remanufacturing Companies (OE data are not
available)
The following table shows the result of an evaluation for the test and diagnosis of electronic
control units.
49
0 5 6 7 10
Table 4: Result of an evaluation for electronic control units (for independent
remanufacturing companies)
System knowledge
Efforts for model creation
Transferability
Failure test
Failure diagnosis
Efforts for automatisation
Invest
Duration of test and diagnosis
Efficiency share
Effort for model creation
Efficiency share
Technical effort
Efficiency share
Economical effort
Efficiency
Main Criteria
Importance in %
40 30 30
Single criteria
Importance in %
37 23 40 40 60 20 43 37
Automatical Optical
Diagnosis 8,0 4,7 6,0 3,3 4,9 10 7,2 8,1 6,4 4,3 8,1 6,3
Bed of Nails Test 1,5 3,6 3,9 8,9 10 10 6,8 8,2 2,9 9,6 8,0 6,4
Clip-Test 1,5 5,0 5,7 8,9 10 2,0 8,7 0,9 4,0 9,6 4,5 5,8
Flying Probe Test 1,5 1,7 3,5 8,9 10 10 1,4 5,5 2,3 9,6 4,6 5,2
Manual Micros-
copic Diagnosis 8,5 8,3 9,1 3,1 3,7 0,0 9,3 1,3 8,7 3,5 4,5 5,9
X Ray Diagnosis 8,0 8,3 9,1 5,0 4,9 2,7 0,6 1,5 8,5 4,9 1,4 5,3
Thermal Imaging 7,8 7,9 9,1 7,7 8,9 8,3 7,0 7,5 8,3 8,4 7,4 8,1
Behavioural Test
8,0 7,0 6,7 9,9 4,9 10 8,2 6,2 7,3 6,9 7,8 7,3
Functional Test 1,5 1,5 3,4 9,9 6,3 10 7,1 8,2 2,3 7,7 8,1 5,7
Artificial Neuronal
Networks 8,5 4,7 5,3 9,9 4,6 8,0 7,0 6,9 6,3 6,7 7,2 6,7
The table above shows a summary of all calculated grades, as well as the efficiency shares
and efficiencies of all methods for the test and diagnosis of electronic control units. The
following figure shows the recommended process steps for the test and diagnosis of
electronic control units.
50
Figure 8: Entrance and final test and diagnosis of electronic control units for independent remanufacturing
companies.
Testing and diagnosing of electronic control units:
Gained
information
• Localized
and
diagnosed
failures
and their
sources
and conse-
quences
• Informa-
tion
concerning
the sorting
of the
systems
for further
steps
Specific
information
resources
• Test and
diagnosis
hard- and
software
• Specifica-
tion (e. g.
connecting
technique,
tempe-
ratures and
their
allowed
tolerances)
Gained
information
• Localized
and
diagnosed
functional
and struc-
tural fai-
lures, their
reasons
and effects
• Information
concerning
the sorting
of the
systems for
further
steps
Specific
information
resources
• Test and
diagnosis
software
• Specifica-
tion (e. g.
input
signals,
test
cases, set
output
signals,
trans-
mission)
for independent remanufacturing companies
Beha-
vioural
Test
Direct Visual
Diagnosis
Thermal
Imaging
Specific
information
resources
• Knowlede
of the
workers
• Specifica-
tion (e. g.
pictures
of good
units,
main
failures
and
FMEA
results)
Gained
information
• Localized,
diagnosed
visual and
structural
failure, their
sources
and conse-
quences
• Information
concerning
the sorting
of the
systems for
further
steps
Systems with not diagnosed failures
Material flow
Systems with non-repairable failures
Systems with diagnosed failures
All systems
51
0 5 6 7 10
4.2.2 OE Manufacturer-related Remanufacturing Companies (OE data
are available)
The following table shows the result of an evaluation of the potential methods for the test
and diagnosis of electronic control units for OE manufacturer-related remanufacturing
companies.
Table 5: Result of an evaluation for electronic control units (OE manufacturer-related
remanufacturing companies)
Table above shows a summary of all the calculated grades, as well as the efficiency shares
and efficiencies of all methods for the test and diagnosis of electronic control units.
The following figure shows the recommended process steps for the test and diagnosing of
electronic control units.
Failure test
Failure diagnosis
Efforts for
automatisation
Invest
Duration of test
and diagnosis
Efficiency share
Technical effort
Efficiency share
Economical effort
Efficiency
Main Criteria Importance in % 50 50
Single Criteria Importance in %
40 60 20 43 37
Automatical Optical Diagnosis 3,3 4,9 10 7,2 8,1 4,3 8,1 6,2
Bed of Nails Test 8,9 10 10 6,8 8,2 9,6 8,0 8,8
Clip Test 8,9 10 2,0 8,7 0,9 9,6 4,5 7,0
Flying Probe Test 8,9 10 10 1,4 5,5 9,6 4,6 7,1
Manual Microscopic Diagnosis
3,1 3,7 0,0 9,3 1,3 3,5 4,5 4,0
X- Ray Diagnosis 5,0 4,9 2,7 0,6 1,5 4,9 1,4 3,1
Thermal Imaging 7,7 8,9 8,3 7,0 7,5 8,4 7,4 7,9
Behavioural Test 9,9 4,9 10 8,2 6,2 6,9 7,8 7,4
Functional Test 9,9 6,3 10 7,1 8,2 7,7 8,1 7,9
Artificial Neuronal Networks 9,9 4,6 8,0 7,0 6,9 6,7 7,2 6,9
52
Figure 9: Entrance and final test and diagnosis of electronic control units for OE Manufacturer-related
remanufacturing companies.
This process combination can be applied for every electronic control unit that is not sealed
with resin material or silicone and that can be opened without destruction. For some parts of
the electronic control unit, the thermal imaging can be used instead of the bed of nails test.
Testing and diagnosing of electronic control units: OE manufacturer-related remanufacturing companies
Specific
information
resources
• Test software
• Process model
of the unit
• Detailed
specification
(e. g. exact set
parameters
and their
permitted
tolerances)
Gained information
• Localized and
diagnosed
functional
failures and
their sources
and
consequences
• Information
concerning the
sorting of the
systems for
further steps
Specific
information
resources
• Test and
diagnosis
software and
hardware (bed
of nails tester)
• Detailed
specification concerning
parts (e. g.
power input)
Gained
information
• Localized and
diagnosed
structural and
functional
failures and
their sources a.
consequences
• Information
concerning the
sorting of the
systems for
further steps
Systems with not diagnosed failures
Functional
Test Bed of Nails Test
Material flow
Systems with non-repairable failures
Systems with diagnosed failures
All systems
53
5 Test and Diagnosis of Actuators and Sensors in
Remanufacturing
The actuators and sensors that are used within mechatronic systems and in vehicles are
nowadays either assembled as electro mechanic systems, as electric systems, electronic
systems or independent mechatronic systems. Lots of actuators and sensors are built in
today’s vehicles. The failure rate in the following table refers to one operating year of the
sensor.
Table 6: Failure rates of vehicle sensors.
Sensor type Sensor application Failure rate
in %/year
Absolute Value Steering angle sensor 0,87
Induktive, Hall-Effect Wheel speed sensor 0,26
Incremental, Hall-Effect Steering wheel angle sensor 0,25
Hall-Effect Acceleration sensor 0,25
Piezoresistiv Break pressure sensor 0,043
Resistiv Throttle valve potentiometer 0,0036
Considering the table above as well as the fact that great amounts of sensors are used in
vehicles, sensors represent a significant failure source.
6 Remanufacturing of Electro Hydraulic Power Steering
Pumps
The reasons for the choice of this system are on the one hand to be found in the relatively
high failure rate and the elevated costs of brand new parts of the electro-hydraulic power
steering pumps (EHPS-pumps) and on the other hand in the feasibility of remanufacturing
the system. For the practical application an EHPS-pumps of the manufacturer TRW is being
used.
54
6.1 Description of the System
Within the electro hydraulic power steering, the steering moment of the driver is decreased
with the help of an EHPS-pump and a rack steering. The following figure shows the
assembly of an electro hydraulic power steering unit of the manufacturer TRW.
Figure 10: Servo steering of the manufacturer TRW (source: TRW Automotive).
6.1.1 Functionality of the EHPS-pump
The following figure shows a sectional view of the electro hydraulic power steering pump of
the manufacturer TRW. In the following, this model will be referred to as TRW_2. The pump
uses steering oil from the tank (1) and, with the help of a cogwheel pump (2) it generates a
load dependent high pressure oil volume flow. The drive of the pump is affected by a
brushless dc motor (4) which is regulated by an electronic control unit (3). A torsion steered
valve (6) within the rack steering (5) lead the generated oil volume flow in such a way that it
supports the drivers steering decision via hydraulic barrels.
55
Figure 11: Electro hydraulic power steering pump of the manufacturer TRW.
6.1.2 Functionality of the EHPS-Pump
The main components of the EHPS-pump are shown in the following figure.
Figure 12: Sectional view of an EHPS-pump of the manufacturer TRW.
(1) Tank
(2) Cogwheel pump
(3) Electronic control unit
(4) DC motor
(5) Rack steering
(6) Valve
(1) Oil tank with refill expansion tank cap
(2) Pressure control valve
(3) Electric connector
(4) Subassembly cogwheel pump
(5) Electronic control unit
(6) Hydraulic connectors
(7) Brushless dc motor
(8) Motorside aluminium case
56
The dc motor (7) is coupled to the cogwheel pump (4). Once set into operation, the
cogwheel pump aspirates the servo steering oil of the oil tank (1) in order to pump it to the
hydraulic connectors (6). The pressure control valve (2) is in charge of the oil pressure
limitation. The inputs to the electronic control unit are the power supply from the battery and
the control voltage from the engine control unit. The three hall sensors that measure the
position and the engine speed of the rotor are integrated in the electronic control unit. With
the help of the external and internal data, the electronic control unit regulates the ramp up,
the operation and the shutdown of the pump.
6.2 Process Steps in Remanufacturing
The remanufacturing of the EHPS-pump is effected according to the six steps of
remanufacturing of mechatronic systems, namely the entrance test and diagnosis, the
disassembly, the cleaning, the test and diagnosis of the subassemblies and parts, the
reconditioning and the reassembly. The entrance test and diagnosis provides important
information about the condition of the system and the subassemblies and in some cases
even about the condition of some parts. Dependent on the result of the entrance test and
diagnosis, the EHPS-system can be remanufactured or has to be material recycled.
All EHPS-pumps are disassembled without destruction. Mechanic subassemblies, as the
cogwheel pump or the overpressure valve are disassembled into their parts. The electronic
control units are not disassembled. All the wear parts like ball bearings, oil filters etc. are
sorted out and passed on to a material recycling. The cleaning of all subassemblies and
parts represents the third step in remanufacturing. The test and diagnosis is carried out for
the electronic control units and parts.
After the test and diagnosis of the subassembly and the parts, the directly reusable
components are placed in storage, while the non-directly reusable components are
reconditioned. The recondition is based on the fixing of the detected, localized and
diagnosed failures. After the reconditioning the mechatronic systems are completely
reassembled. During this method, the wear parts are always replaced by new ones.
All steps of remanufacturing are constantly supervised by a quality controller. Before the
systems were sold, all the EHPS-pumps go through a 100 % final test and diagnosis. The
steps of disassembling, cleaning, reconditioning and reassembling are comparable to the
remanufacturing of mechanical systems.
57
6.3 Entrance and Final Test and Diagnosis in Remanufacturing
6.3.1 Choice of Methods
The remanufacturing process consists of the selected methods mentioned above. With
regard to independent remanufacturing companies, the combination of the two signal based
methods, the direct optical diagnosis, and the characteristic curves, has presented itself as
the best solution. With regard to manufacturer-related remanufacturing companies the
parameter estimation has been preferred to the characteristic curves test, since it provides a
greater range of failures. The EHPS-pump can be regarded as black box and characterised
on the basis of its input and output signals. The following figure shows the relevant input and
output signals of the EHPS-pump.
Figure 13: EHPS-pump as black box system.
Based on the measured input and output signals, the characteristic curves reflecting the
function of the system, can be measured.
6.3.2 Construction of the Test Bench
Accomplishing the characteristic curves test, requires an automated industrial test bench,
which has to be developed, produced and put into operation. The following main tasks are
assigned to the test bench:
• Simulation and control of the environmental conditions in order to enable every
operation point of the EHPS-pump.
ECU Voltage Input
Pump Voltage Input
Pump Current Input
Measurement
Oil Volume Flow
Pressure ECU Current Input
EHPS-Pump
as Black Box
System
58
• Measurement of the input signals and output signals of the EHPS-pump and the
environmental conditions.
• Evaluation of the results.
The construction of the test bench is done with the computer aided design (CAD) program
Pro/ Engineer Wildfire. The following figure shows the CAD-model of the test bench.
Figure 14: Construction of the test bench for EHPS-pumps.
The required main components, as for example the power supply, the volume flow sensor,
the pressure sensors, the proportional control valve, the oil filling pump, the control and
measuring software are provided by suppliers. In order to simulate the environmental
conditions at the test bench, the oil volume flow is restricted by a proportional control valve.
The following figure shows the real construction of the industrial test bench for EHPS-
pumps.
59
Figure 15: Industrial test bench for EHPS-pumps.
6.3.3 Running the Tests
The core pump is electrically and hydraulically adapted to the test bench. This adds up to a
clamping time of about 10 seconds per EHPS-pump. On the PC, the operator is able to
access to already existing test cycles and specifications of the data base, or they can define
new ones. Now the system is automatically filled with servo steering oil. By regulating the
proportional control valve, the test cycle moves the EHPS-pump into the defined operating
conditions. The hydraulic environmental conditions of the test bench simulate the real
EHPS-pump conditions in the vehicle.
With the help of the input and output signals, the test bench calculates operating points.
Those are then compared to the allowed specifications. The collected measured data are
saved for the quality assurance on the personal computer. The measured data are printed
automatically. This data offers important information for the further remanufacturing steps.
After the test has been completed, the servo steering oil is automatically pumped off the
core, so that the EHPS-pump can be removed from the test bench, which may take up to
another 10 seconds of unclamping time. A test that includes clamping and unclamping,
filling, measurement, evaluation and cleanout requires about 60 seconds time, depending
on the number of examined points.
60
6.3.4 Test Bench Results
The determined characteristic points of the EHPS-pumps are interconnected to a
characteristic curve which serves as test result. The following figure shows the characteristic
curves (volume flow, input power, output power and efficiency through pressure) of a new
EHPS-pump of the manufacturer TRW.
Figure 16: Characteristic curves of a new EHPS-pump of the manufacturer TRW.
By slowly closing the control valve, the pressure of 4 bar (which corresponds to the minimal
loss of pressure within the system) arises to a maximum of 88 bar, which corresponds to the
maximum pressure of an EHPS-pump which is controlled by a responding internal limitation
valve. The characteristic curves of the EHPS-pumps can be divided into the following four
sections:
• 4 to 17 bar: „waiting range “with a constant volume flow, increasing input and output
power and intensely increasing efficiency.
• 18 to 28 bar: „activating range “with rising volume flow, rising input and output power and
nearly constant efficiency.
• 28 to 80 bar: „working range “with decreasing volume flow, increasing input and output
power and nearly constant efficiency.
Pressure in bar
Pressure in bar
Pressure in bar
Pressure in bar
Volume flow in 1/min
Input power in W
Efficiency in %
Output power in W
61
• 80 to 88 bar: „over pressure range “with decreasing volume flow, decreasing output
power and efficiency and increasing input power.
After the activation of the input signals, twelve out of the 106 cores have not shown any
reaction. The following figure shows the calculated characteristic curves volume flow
through pressure of the 94 working EHPS-pumps.
Figure 17: Characteristic curves of 94 working EHPS-pumps.
Only one EHPS-pump clearly shows a less volume flow and a maximum pressure lowered
by 50%.
6.3.5 Determining the Specifications for Remanufacturing
EHPS-pump manufacturer specifications concerning the test and diagnosis are generally
not available. In order to determine specifications for the EHPS pumps, in-situ
measurements are carried out during various driving experiments.
Therefore, a new EHPS pump is installed in a test vehicle. In order to characterize the
EHPS pump during the driving experiments, the inputs and outputs have to be measured in
the same way compared with the test bench. Voltage sensors, power input, volume flow and
pressure sensors as well as the measured value acquisition that is carried out with the help
of a laptop with PCMCIA-card are also installed in the vehicle. Since the TRW_2 EHPS-
Volume stream in l/min
Compression in bar
62
pump is mainly installed in the Opel Astra G, this vehicle type is the one used for the real
road tests. The tests are carried out on a test territory that is not accessible for the public.
The following figure shows the passenger compartment with the driver and the measured
value acquisition (left) and the test vehicle on the test territory (right).
Figure 18: In-situ measurements during driving experiments in order to determine specifications.
A total of 10,000 operating points within the different ranges of the EHPS-pumps are
examined. The following figure shows the calculated specifications for six operating points
(P1 too P6).
Table 7: Specifications for the EHPS-Pumpe (Type TRW_2).
P 1
(5bar)
P 2
(30bar)
P 3
(50bar)
P 4
(65bar)
P 5
(80bar)
P 6
(85bar)
Volume flowmin in l/min 3,8 3,8 3,8 3,75 3,3 0
Volume flowmax in l/min 5 5 4,75 4,25 3,75 3,6
Power Inputmin in W 20 320 540 620 680 680
Power Inputmax in W 100 420 600 700 760 760
Power Outputmin in W 30 190 320 410 440 0
Power Outputmax in W 45 250 400 460 500 500
Efficiencymin in % 20 50 55 55 55 0
Efficiencymax in % 45 75 75 75 75 75
6.3.6 Results of the Characteristic Curves
The following figure shows the characteristic curves of 94 EHPS-pumps as well as the
defined specifications.
63
Figure 19: Characteristic curves of 94 EHPS-pumps and specifications.
The figure above shows clearly that two units exceed the defined tolerance ranges while two
other systems are at the tolerance limits. The entrance tests and diagnoses of the EHPS-
pump show the result that 12 pumps do not display any function and that some operating
points of four other pumps are not within the specifications. The great amount of working
systems is to be based on the fact that the majority of the tested systems had been removed
from accident vehicles, in which the EHPS- pump did not come to any harm. The core
suppliers do not remove or sell obviously damaged EHPS-pumps to remanufacturing
companies. During the test and diagnosis of the EHPS-pumps, the functionality of the
systems is examined with the help of the specially designed test bench, focussing on the six
characteristic points. This assures a safe and economic way for the test and diagnosis.
6.4 Summary
The test and diagnosis of the electro hydraulic steering pump is carried out with the help of
the combination of the two signal based methods direct visual diagnosis and calculation of
the characteristic curves. In order to perform the calculation of the characteristic curves, an
appropriate test bench has been developed and used.
0
0,5
1
1,5
2
2,5
3
3,5
4
4,5
5
0 10 20 30 40 50 60 70 80 90 Druck in bar
Volumenstrom in l/min P 3
P 5
P 4
P 6
P 2 P 1
Volume flow in l/min
Pressure in bar
64
On the basis of input and output signals, this test bench is able to investigate the
characteristics of the system.
The input and output signals of the mechatronic system with regard to changes of the
environmental conditions (e. g. the load) are measured at the test bench. Operating points
and characteristic curves are calculated. In order to investigate specifications, in situ-
measurements had been carried out during several real road tests. Specificationss are then
defined in form of permitted tolerance ranges for the characteristic curves of the electro
hydraulic power steering systems.
In order to shorten the total duration of the test and diagnosis, five characteristic points and
their tolerance limits are selected. With their help, the systems can be diagnosed and their
proper functionability can be measured.
7 Remanufacturing of Electronic Control Unit of an
EHPS-Pump
7.1 System Description
The electronic control unit of the electro hydraulic steering pump (EHPS-pump) regulates
the start up, the operation and the shut down of the brushless motor, which is directly
connected with the cogwheel pump. The motor is constructed as an outboard motor, whose
permanent magnets are situated within the rotor and the coils within the stator. The following
figure shows the electronic control unit.
65
Figure 20: Electronic control unit of the EHPS-pump.
The stator coils are closely interconnected with the electronic control unit and cannot be
separated from it without destruction. Furthermore the two hall sensors are assembled on
the circuit board. The battery voltage and the control voltage are adjacent to the entrance
pins. The four exits of the electronic control unit are directly interconnected with the stator
coils. They represent the exits of the four power transistors. Via the power transistors, the
power, the magnetic field within the coils, the revolution speed and the torque of the motor
are regulated.
7.2 Test and Diagnosis for Remanufacturing
The test and diagnosis of the electronic control unit is the fourth step in the remanufacturing
process of mechatronic systems. During the first step of the process chain, the mechatronic
systems are tested and diagnosed, as described. Thereupon, the system is disassembled
into the electronic control unit and the further parts. During the third step, all subassemblies
and parts are cleaned by different methods. The cleaned electronic control units are then
passed on to the fourth step of the remanufacturing process chain, the test and diagnosis of
subsystems and parts.
7.2.1 Choice of Methods
The combination of the methods behavioural test, thermal imaging and direct visual
diagnosis has proved itself as the most suitable solution. The behavioural test is carried out
66
before the thermal imaging, in order to determine if the core has failed or not. The
behavioural test compares the output signals of the unit dependent of the used input signals
with output signals of a reference unit. Therefore the behaviour of the unit dependent on the
used input signals has been used for the test. The failed cores are passed on to the thermal
imaging, in order to locate and diagnose as many failures as possible with their sources and
consequences. The recognized failures, as for example faulty transistors, broken contacts
and connections etc., are repaired during the following step of reconditioning. Afterwards, a
further behavioural test will examine if the proper function of the unit has been
reconstructed. If further failures are detected, a process is set off in order to locate, diagnose
and repair every failure. The procedure is finished as soon as there are no failures which
can be detected during the thermal imaging.
7.2.2 Construction of the Test Bench
The application of the method thermal imaging within remanufacturing is based on the
comparison of thermal images of cores and new units (references). In order to assure the
comparability of the images, all thermal images have to be made under similar
environmental conditions. Especially with regard to the thermal imaging of electronic control
units, the attention has to be paid to the following environmental conditions:
• Comparable entrance temperatures and distribution within the unit.
• Comparable surface qualities of the units through cleaning.
• Comparable input signals to operate the units.
• Comparable stress of the unit exits.
• Comparable environmental conditions concerning temperature and humidity.
• Neglectible thermal radiation of the environment.
• In the moment of recording: comparable turn on time for the units.
• Same settings of the thermal imaging camera.
In order to create the comparable environmental conditions mentioned above, a simple test
bench is used for thermal imaging. In a defined distance, the camera is fixed on a rail which
runs vertically to the surface of the units. The electronic control unit is attached to an adaptor
and charged with the load of the engine rotor. The adaptor, the electronic control unit and
the rotor are set into a steel case, which is painted black on the inner side, so that only a
neglectible thermal radiation can interfere the measurement. Through a gap on the front side
of the case, the thermal imaging camera can record the images. The following figure shows
the test bench including the camera which was used as well as the steel case, in which the
electronic control unit is located.
67
Figure 21: Test bench for the thermal imaging of electronic control units.
7.2.3 Determining the Specifications for Remanufacturing
The method of statistical evaluations of the new original systems is used for defining
specifications for thermal imaging. In thermal imaging the comparison of reference and core
unit temperatures are used in order to locate and diagnose failures. As a first step, the
average reference temperatures of essential regions of the reference units are measured.
As a second step the definition of the permitted tolerance limits for every essential region
follows. In order to stipulate the permitted tolerance limits, the empiric standard deviation is
used. The empiric standard deviation “s” converges against the root mean square deviation,
according to the increasing number of measured data. The maximum allowed average
temperature of one region of the core is defined to the average temperature “T” of the same
region of the reference unit plus three times the empiric standard deviation of that region.
The minimum allowed average temperature of one region of the core is defined to the
average temperature of the same region of the reference unit minus three times the empiric
standard deviation of that region.
Average temperature: ∑=
⋅=N
i
iT
NT
1
1
Empiric standard deviation: ( )∑=
−⋅−
=N
i
iTT
Ns
1
2
1
1
Results show that the needed turn on time for the units is about 30 seconds. The stipulated
specifications are only valid for the tested electronic control unit and the defined
68
environmental conditions. For further units and environmental conditions, the specifications
can be determined in the same way.
7.2.4 Performing the Tests
The electronic control unit to be tested is mechanically interconnected. The rotor is linked
and the entrances of the units are electrically connected with a power supply unit. The
metallic rotor is painted black, in order to prevent any reflection of radiance. The entire
construction is covered with a steel case, in order to shield foreign radiance. The camera is
fixed within the defined distance from the units. The power supply unit provides electrical
power to run the electronic control unit. After 30 seconds, the thermal image of the
temperature on the electronic control unit is recorded. After that, the unit can be
disconnected from the power supply unit and it can be dismantled from the test bench.
Altogether, a thermal image requires about 40 second’s time.
7.2.5 Measured Results
The following figure shows a thermal image of a reference unit.
Figure 22: Photographic recording of the electronic control unit and a superimposed thermal image.
For the evaluation of the images the following methods are possible:
69
• Manual comparison of temperatures at all essential regions
• Automatic comparison of temperatures at all essential regions
For the evaluation of the cores, all average temperatures at all essential regions of the cores
have to be compared with the specifications. With the help of expert knowledge, failure
trees, typical failure representations etc., the thermal visible failures within the electronic
control unit can be located and diagnosed. Good system knowledge of the worker and a
minor complexity of the unit have positive effects on the percentage of localizable and
diagnosable failures and their consequences. To minimise the effort an excel sheet is
programmed which automatically defines the specifications and compares the cores with the
references. The software locates all discrepancies between the temperature of the core and
the specified temperature.
The first sequence shows the photographic recording of the electronic control unit (left) and
the superimposition of the photographic recording by a reference thermal image (right). The
two figures in the lower sequence show the superimposed figures of failed electronic control
units. The respective area where the faulty element is located is marked by a black square,
while the area where the consequence is located is marked by a black oval.
70
Figure 23: Photographic and thermal image of electronic control units.
The figure above shows that failures and their consequences can have significant and
clearly visible effects on the temperature distribution within the unit. The following figure
shows an example of thermal image that require a change within the temperature scale of
the figure in order to offer an exact localization and diagnosis of the failures and their
consequences.
71
Figure 24: Same thermal images of an electronic control unit with different temperature scales.
Through the change of the temperature scale, from a range of 19°C to 31°C (see upper
figure) to a range of 10°C to 90°C (see lower figure), the failed part can be located more
exactly. The error that is shown here is a short circuit within a diode, caused by a metal
particle.
The thermal imaging makes it possible to recognize the failures of the cores. Based on the
thermal imaging, 80 percent of the existing failures within the electronic control units could
be localized and diagnosed.
7.3 Summary
The electronic control unit of the EHPS-pump, the stator of the motor and the hall sensors
are structurally gathered on a unit. The four exits of the electronic control unit are the exits of
the four power transistors that are directly interconnected with the stator windings. For the
72
test and diagnosis of the electronic control units, a combination of the behavioural test, the
thermal imaging and the direct visual diagnosis is applied.
The specifications for the thermal imaging are determined via statistic analyses of new
electronic control units. Therefore, the average temperature and the empiric standard
deviations of the measured temperatures at essential regions of reference units are
investigated to find out the specifications. A symmetric tolerance band with tolerance
broadness of three times the empiric standard deviation around the average temperature is
used as specifications for every essential region.
The evaluation of the images is effected via manually and automatically comparison of core
temperatures at essential regions of the electronic control unit and the specifications for
these regions. In 80% of the cases, the diagnosis, based on the thermal image, leads to a
localization and diagnosis of the failures. Therefore, the method of thermal imaging
represents itself as technically and economically highly suitable method for the test and
diagnosis of electronic control units of EHPS-pumps. In cooperation with several
remanufacturing companies, the method of thermal imaging has already been transferred to
further electronic control units like motor control units.
8 Remanufacturing of Air Mass Sensors
8.1 Description of the System
The mass air flow sensor or mass air flow meter (MAF) is used within the vehicle in order to
measure the actual mass-flow of the air which is aspirated by the internal combustion
engine. The sensor is to determine the exact amount of oxygen that is actually flowing into
the engine. In contrast to the originally used volume air flow sensor, the mass air flow sensor
integrates the data of temperature and air humidity, in order to calculate the actual air mass
and not only the volume. This mass is then communicated to the engine control unit and it is
decisive for the proportioning of the fuel for the motor.
With regard to the mass air flow sensor comes up the decision whether to take the originally
used hot wire MAF sensor and the contemporarily used hot film MAF sensor. Whereas for
the hot wire MAF sensor, the air mass is determined with the help of two platinum wires, the
hot film MAF sensor is based on a resistant bridge circuit on a ceramic plate. Depending on
its type, the sensor consists of a heating resistor, several balancing resistors, some auxiliary
resistors and one sensor resistor. The sensor resistor is warmed up by the heat resistor,
affected by the surrounding air mass. The balancing resistors exclude any influence of the
air temperature on the measured result. Via skilful linking of the resistors as Wheatstone
73
bridges, the dependence of the sensor resistor on the surrounding air mass can be
recalculated. The following figure shows the exploded assembly drawing and a view of an
open MAF sensor case.
Figure 25: Hot film mass air flow sensor of the manufacturer Bosch.
Within the vehicle, the MAF sensor is directly installed behind the air filter. All the particles
(oil, dirt, water etc.) that are not sorted out by the air filter, flow through the mass air flow
sensor. They can settle down on the hot sensor plates and therefore falsify the measured
size of the air mass. This means that the air mass sensors provide incorrect data. Wrongly
measured air masses cause faulty calculations of the needed fuel amount for the engine
controller, so the motor cannot work according to its optimum. Among others, there are the
effects of lower engine power, worse exhaust fumes, higher fuel consumption and even
sporadic breakdowns of the motor.
Partly because of the high failure rates and the elevated prices of mass air flow sensors
these subassemblies are especially suited for remanufacturing. The following paragraphs
will focus on the remanufacturing of the Bosch mass air flow sensors, as a representative for
the many different types of mass air flow sensors in vehicles.
(1) Coverage of the measuring channel
(2) Thin layer sensor
(3) Holder tin
(4) Electronic case coverage
(5) Electronic control unit
(6) Electronic case
(7) O ring seal
(8) Temperature sensor
(1)
(4)
(5)
(6) (7)
(8)
(2)
(3)
74
8.2 Process Steps in Remanufacturing
The first step within the remanufacturing of a mass air flow sensor is the entrance test and
diagnosis. The cleaning of the sensor element and of the case can be effected without any
disassembly of the coverage. Because of the high integration level of the electronic control
unit and the imbed mass that cannot be removed without destruction of the unit, structural
failures cannot be repaired economically. If errors on the characteristic lines are detected
during the entrance test and diagnosis, they can partly be repaired by the software within the
step of reconditioning.
For the reasons mentioned above, the remanufacturing of air mass sensors mainly consists
of the steps entrance test and diagnosis, cleaning and reconditioning by software update.
After the accomplishment of these processing steps, a final test and diagnosis is carried out
as for any other remanufactured product. If it is proved that the remanufactured MAF sensor
works correctly again, it can leave the remanufacturing company.
8.3 Test and Diagnosis in Remanufacturing
8.3.1 Methods
With the help of the direct visual diagnosis the sensor is mainly examined for external
damages. The primary method for the test and diagnosis of the mass air flow sensors the
behavioural test has been used.
8.3.2 Construction of the Test Bench
The main task of the test bench is a simulation of the surrounding conditions, a
determination of the operating points, a measurement of the inputs and outputs and an
evaluation of the measured values. Further requirements are a short running time as well as
flexibility and a high exactness of the measured values. The flexibility is related to the
geometry and the measurability of the high variety of mass air flow sensors that are installed
in vehicles. Given the speed and the cylinder capacity, the required air mass flow can be
assessed with the help of the following formula:
H
MV
nVm ⋅⋅⋅=⋅=
602
1ρρ &&
75
A cylinder capacity of 2,5 litres (0,0025m²) and speed of 6500 revs per minute are assumed
as the maximum variables of the vehicle volume models, as well as an atmospheric
pressure of 1,2kg/m³ at 20°C. With this data, the formula given above calculates an air mass
flow maximum of 585 kg/h. The required air mass flow is generated by a two leveled lateral
channel blower. It can be tuned between 0kg/h and 625 kg/h by two steerable valves and by
a frequency converter for the motor. Depending on the valve positions and the speed of the
blower, it is possible to generate a vacuum between 0 and 320 mbar. Furthermore, the air
temperature which is flowing through the mass air flow sensors at the test bench, can be
regulated between the surrounding temperature and + 60°C with the help of an air heater.
For the behavioural test, the sensor output voltage of a core MAF sensor and a new
reference MAF sensor are compared with regard to several operating points. There are two
principal possibilities in order to determine the reference output voltage. On the one hand,
the physical reference MAF sensor can be fitted in-line with the core at the test bench, so
that the reference output voltage and the core are measured simultaneously. On the other
hand, it is possible to pre-determine the reference voltage with the help of a reference MAF
sensor and to store this reference voltage into the test bench software. The two test
concepts offer the advantage that the current air mass flow does not have to be measured
by an extremely expensive sensor. The following figure shows the test bench construction
made in Pro/Engineer with its main components.
Figure 26: Constructed air mass sensor test bench
(1) Air heater
(2) Blower
(3) Air mass sensors
(4) Valves
(5) Switchboard
(6) Control cabinet
(7) Screen
(8) Printer (5)
(1)
(2)
(7)
(8)
(6)
(4)
(3)
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In the control cabinet (5) are located among others the PC, the frequency converter, the cabling, as well as further measurement-, regulation- and controlling assemblies. The blower
(2) pipes a part of the total air mass flow, depending on the position of the two valves (4), the
air heater (1) and the two mass air flow sensors (3).
Figure 27: Applied industrial test bench for air mass sensors.
8.3.3 Test Results
With the test bench described, 75 similar used MAF sensors of one type are tested. All the
MAF sensors had already been used within customer vehicles. During the test,
characteristic points within the entire operating range (each in 5% distance) are brought up
to between 0 and 100% by a gradual rising of the volume flow. The tests are performed at
various temperatures.
For every operating point, the relative divergence between the core and the reference output
are calculated. Based on these relative divergences, the maximum relative divergence is
determined for every mass air flow sensor (see following figure). One of the 75 MAF sensors
has a mechanically destroyed case, another some plugs and connecting pins that are
destroyed in such a way that the air mass sensors have to be sorted out in advance.
77
Figure 28: Maximum relative divergence of 73 used mass air flow sensors.
Some of the mass air flow sensors have a relative deviation of more than +/- 10% which cannot be completely presented in the figure above.
8.3.4 Evaluation of the test results
The following figure shows the maximum deviations of the examinee and reference outputs during the entrance test and diagnosis, as well as possible determinations of specifications.
Max
imum
rela
tive
dive
rgen
ce in
%
73 Air Flow Sensors
78
Figure 29: Maximum relative deviation of 73 used mass air flow sensors and proposed tolerance
ranges.
Within an admissible tolerance range of +/- 5%, 33 out of 73 tested mass air flow sensors
(45%) are reusable without remanufacturing. If the tolerance range is set down to +/- 3%,
there are 10 directly reusable sensors out of 73 (14%). In order to reach a quality level that
is similar to the one of an original part, a permitted tolerance range of +/- 3% is
recommended. Result:
• Two air mass sensors cannot be reconditioned.
• Ten air mass sensors can be directly reused.
• The remaining 63 air mass sensors go through the remanufacturing process steps.
There are several reasons for the number of directly reusable systems. The input of cores to
remanufacturing companies does not only consist of defective units, since some of the cores
are dismantled from accident vehicles whose air mass sensor works accurately. Another
important reason is that up to 80% of the electronic control units and sensors are replaced
by a wrong diagnosis in the garages. The correlation described above can not only be
discovered with regard to mass air flow sensors, but also concerning many other electronic
control units.
Tolerance range of +/- 7% +/- 5%
+/- 3%
Max
imum
rela
tive
devi
atio
n in
%
10 pieces
33 pieces. Directly reuseable systems: 50 pieces.
73 Air Mass Sensors
79
8.4 Summary
Because of the relatively high failure rate and the high costs for new mass air flow sensors,
these systems are very promising for remanufacturing. The remanufacturing of the sensors
that are constructed mainly as electronic control units consists of the steps entrance test and
diagnosis, cleaning and reconditioning, followed by a final test and diagnosis. The signal
based procedure of the behavioural test is applied for the test and diagnosis in the entrance
and final test. The developed and built up test bench allows an economically sensible test
and diagnosis of failures, for mass air flow sensors.
On the basis of 75 used and one new hot film mass air flow sensor of the same type, the
function of the test bench, the determination of the specifications, as well as the evaluation
of the measured results et al. are exemplified. The specifications are based on available
original specifications. The used mass air flow sensors can be divided into directly reusable,
reusable after remanufacturing and not reusable ones on the basis of the specifications and
the evaluation of the entrance test and diagnosis.
After the cleaning and the reconditioning the mass air flow sensors have to pass a final test
and diagnosis, which is carried out in the same way as the entrance test and diagnosis.
9 Conclusion and Outlook
Rising requirements for modern vehicles concerning comfort, safety, sustainability and
costs, have especially in the last decade led to a widespread use of innovative mechatronic
systems. The high complexity, the mass of interactions, the great variety of versions and the
high speed of the technical innovations of mechatronic systems, provides a particular risk for
the smooth functioning of systems and the reliability of modern vehicles. Today’s garages
use on-board-diagnosis functions to detect failed mechatronic systems. Even reputable
garages cannot repair them and therefore have to replace the systems mainly with new
ones.
It is common to remanufacture mechanical and electro-mechanical systems of vehicles.
Remanufacturing offers the same quality and reliability as a new product for lower costs.
The five known remanufacturing process steps, which are disassembly, cleaning,
inspection, reconditioning and reassembly, have to be supplemented for the
remanufacturing of mechatronic systems by a new first step which is the entrance diagnosis.
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The most challenging steps in remanufacturing mechatronic systems are the entrance
diagnosis of the complete mechatronic system and the inspection of the electronic, sensor
and actuator subassemblies. A further difficulty is caused by the insufficiency of the
technical information, especially in the field of test specifications. Still, the complete system
and subsystem tests require that test specifications are available.
Independent remanufacturing companies could explore the test specifications by using the
following resources:
• Statistical analyses of new, original systems.
• Reverse engineering of original systems.
• In-situ measurements in road tests.
The main questions for the two steps entrance diagnosis and inspection are, which test
methods and test sequences are the best choice. The special boundary conditions, like high
variety of versions, low quantities, limited know how of the system, limited capital investment
etc. in remanufacturing companies, have to be included in the decision. To characterize the
feasible test methods to be used in remanufacturing, a value-benefit analysis of the most
promising signal-based, signal model-based and model-based test methods was carried out.
The final results of the chosen test methods and test sequences for independent and
OEM/OES-cooperating remanufacturing companies are summarized in the following table.
Table 8: Chosen test methods and test sequences in remanufacturing.
Entrance and final diagnosis of:
Complete mechatronic systems as
well as mechatronic actuators and
mechatronic sensors
Inspection of:
Electronic control units as well
as electronic actuators and
electronic sensors
Independent
remanufacturing
companies
Direct Visual Diagnosis
+
Behavioural Test
Behavioural Test
+
Thermography Imaging
+
Direct Visual Diagnosis
OEM/OES-
cooperating
remanufacturing
companies
Direct Visual Diagnosis
+
Parameter Estimation
Functional Test
+
Bed of Nails Test
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The test methods and test sequences in the table above as well as the resources to explore
the test specifications have successfully been adopted, in cooperation with different
European remanufacturing companies, for different sample systems.
Out of the mass of mechatronic systems in today’s vehicles, a preliminary inquiry shows that
electro-hydraulic power steering pumps are predestined for remanufacturing. Therefore 200
used electro-hydraulic power steering pumps (“core”) were collected and analyzed with the
behavioural test in the entrance and final test in the remanufacturing process. The required
test specifications were discovered by in-situ measurements in road tests with an Opel Astra
G on a suitable test area. To perform the behavioural test, a proprietary test bench was
developed and built, which is now introduced in the industrial remanufacturing process of a
co-operation partner. The test procedure is based on the comparison of the core behaviour
with the defined specifications of characteristic operating points.
To show that the applied method of thermal imaging can be used for failure detection and
isolation in the remanufacturing process step of inspection, 36 electronic control units
(electronic subassemblies) of the electro-hydraulic power steering pumps were selected.
Test specifications were calculated by statistical analyses of new, original systems. The
results of the thermal imaging were that the failures on the electronic control units could be
detected and 80% of the failures could be isolated on the bases of the thermal images.
The last practical example involved 75 air flow sensors, which are today mainly constructed
as electronic units. The known original specifications could be used. For the inspection of
the sensors, an automated test bench was developed and produced. The test of the sensors
is based on the behavioural test and compares the behaviour of the used air flow meters
with the original specifications at different operating points.
The applied and demonstrated methods of finding out specifications as well as the
determined test methods and test specifications for the entrance, final test and the
inspection contribute to the technical and economic feasibility of remanufacturing of
mechatronic systems.
Further research could discover the specifications of and provide test methods for
mechatronic systems with complex external bus systems. A further specific aspect is the
automation of thermal imaging to achieve an accurate, reproducible and reliable industrial
test in remanufacturing companies. A very interesting final point is the estimation of the past
life time and the remaining life time of cores, which appears promising by a further
development and application of the parameter estimation and the thermography imaging.
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83
SUSTAINABLE DEVELOPMENT BY REUSING USED AUTOMOTIVE ELECTRONICS
Research Project ReECar performed by Fraunhofer Institute for Reliability and
Microintegration, IZM , Berlin (Germany)
By Fernand Weiland, responsible for the content which is based on Information
communicated by Fraunhofer IZM.
1. Introduction
The ReECar Project is funded by the German Minister for Education and Research to
support efforts to promote sustainable development by creating a basis to facilitate the
reusing of old/used automotive electronic components. The Fraunhofer IZM (an Institute
specialized in researching the reliability of electronic assemblies and micro components) is
leading the project in conjunction with the automotive Tier 1 partners Continental
Automotive Systems and Hella KgaA Hueck & Co, as well as logistic partners, Callparts
System GmbH, Fraunhofer Institute for Material Flow and Logistics IML and Retek AG .
Figure 1: Source: Fraunhofer IZM Berlin.
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With the advent of mechatronics, and due to their short design cycles of approximately five
years, in the future it will be very difficult for the automobile industry to provide service
replacement parts for the entire life of a car model, which could be up to 20 and more
years! To cope with this challenge the manufacturers have only a few alternatives: long
term storage, periodic manufacturing, downward compatibility or reusing or
remanufacturing old/used components.
2. Objectives
The overall objectives of the research were to support the efforts of the German
automotive industry to develop a sustainable environment by:
• encouraging the reuse of used automotive components
• creating specifications and recommendations on how to reliably reuse the used
components
The main proposed steps to achieve these objectives are:
• to develop a methodology to assess the environment a sustainability of different
proposed strategies
• to assess the feasibility of using old/used components
• to develop processes on how to determine the health/conditions of used/old
components
• to create guidelines on how to design electronics in order to make them suitable for
reusing/remanufacturing
• to promote the reusing/remanufacturing of components for ongoing automotive service
requirements and for supporting the challenging requirement of covering exceptional
long term service requirements
footnote from the editor
For our industry, remanufacturing is the preferred alternative. Remanufacturing is a safer process than
simply reusing the component without processing it. It is the most economic alternative and it is a process
which has no life cycle or time restrictions. Remanufacturing can be performed at any time in the life time of
a car!
85
3. Developing processes to assess the health/condition of used components
For components which are intended to be reused as electronic automotive controllers, it is
vital to know their health before they are reused in remanufacturing. To assess the
conditions/health of components the Fraunhofer IZM proposed:
• to investigate how to qualify the used components
• to research methods to assess the quality of the components
• to research which data are required to make quality assessments of components
(mileage, production year, etc)
• to investigate how the environment (temperature, vibration etc ), over time, can affect
the components
To achieve above objectives, the Fraunhofer IZM has arrived at the conclusion that they
need to perform the following tasks:
• to propose tests which are a combination of functional and stress temperature tests
• to investigate the performances of electrolytic capacitors over time
• to analyze solder interconnections
• to investigate how humidity affects the components over time
The photos below are an example on potential defects which can, in the worst cases,
appear in solder interconnections.
Figure 2: Source: Fraunhofer IZM Berlin.
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4. Specific investigation of Automotive used electronic components
IZM, Continental Automotive and Hella have performed preliminary tests on 10 year old
used components procured from approximately 10 year old cars. The objective was to find
out how old units perform after having been in operation in passenger cars. The tests were
run under the same conditions used for new units and the results were compared with the
performances of new units from stock.
4.1 Testing Long Term stored Central Electronic Control Modules from Continental
For a Mercedes type E, some used units, but most stored new units, produced in 1996
(see photo below) were selected, tested and dismantled for visual checks. The results of
these tests and checks proved that the performances were still in line with the original
specifications. Only minor whiskers were found in tin-plated conductors of the stocked
units, but the same irregularities were also found on used units.
The used units tested had been selected from a batch of units with some external
damages or dirt, but this was not regarded as a major defect, since these “defects” can
easily have been fixed during remanufacturing and did not influence the performances!
Figure 3: Source: Continental AG.
87
4.2 Testing used ABS modules from Continental Automotive Systems
As in the previous tests, the old units used were selected from a batch of old, used units
which had some dirt and small damages to the plastic cases. The objective of the
proposed tests was to run several stress tests to find out if the performances or the
electronic modules would change and deteriorate. An initial test showed that all the units
were functioning.
Figure 4: Source: Continental AG.
To start with the stress program all the used units were put to a thermal test, which
consisted of 50 cycles and a 2 ° Celsius temperature change every minute. Following this,
the next step was to run a test for 450 hours at high temperature (110° Celsius) and
perform a functional test every 30 minutes. The final test was a thermal shock test where,
during one hour, the temperature went from –40° to 110 ° Celsius. All units passed all
these tests successfully!
Last but not least, vibration tests were performed for three axis’s during eight hours.
Humidity tests for 500 hours at 85° Celsius and 85 % relative humidity were also carried
out. The positive news was that all units tested passed all the tests successfully! More
extensive tests are currently underway; however, the above tests have already shown how
reliable old Continental units are.
Footnote from the editor
The quality of the old/used units can be high enough that they can be reused without risk, provided they
undergo proper remanufacturing, which consists of cleaning, inspecting, testing the units, changing critical
components and when required, changing damaged connectors.
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4.3 Testing automotive cockpit Electronic controllers from Hella
Fifty old/used electronic controllers from Tier 1 manufacturer Hella were removed from old
used cars and were tested and checked for the following potential failures/defects:
• degradation of solder joints, solder interconnections and printed circuits
• bad performance of aged capacitors and certain selected semi-conductors
• increased electrical resistance of the relays and connectors
• changed properties of plastic materials
Figure 5: Source: Hella KgaA Hueck & Co.
The function tests were all positive and between a controller with a mileage of 10.000 and
150.000 km no difference was found. An aging or a significant alteration of the latter one
was not found either. Detailed results are available from Hella who will now submit these
units to stress tests, similar to the ones carried out on the Continental modules (see 4.1) .
The final results will be communicated at a later date.
Final note from Editor
The project was not completed at the time of issuing this report. Final results will be communicated by
Fraunhofer IZM at www.ReECar.org. Without trying to pre-empt the final results, one must admit that the
tests performed to date are very encouraging, confirming that remanufacturing electronic controllers is a very
viable solution for reusing automotive electronics.
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RESEARCH OF INTERNET & SCIENTIFIC DATABASES ON REUSING AND INSPECTING USED ELECTRONICS
By Fernand J. Weiland, FJW Consulting, Cologne (Germany)
1 Preface
Internet research was performed using words such as PCB reuse, PCB recycling, solder
joint, BGA reliability, electrolytic capacitor failure, conductor path reliability etc. As a result,
around 500 hits were registered. In addition a research of relevant scientific data bases
was achieved. Most of the sources found were however related to new production and the
related potential defects and failures. Among the discovered data, the most relevant
information involved failure rates and life time expectancy.
An important process with the reuse of circuit boards is firstly, the assessment of the state
of the components and secondly, the evaluation of whether the board can be reliably
reused for remanufacturing. For this reason, the most frequent failure mechanisms and
methods to diagnose them will be presented in this report.
90
Figure 1: Basic procedure for inspecting electronics.
2 Basic information on the reuse of circuit boards
A manufactured circuit board ordinarily involves several dozens of active and passive
elements and components, with around 1000 solder joints. The present European
directive, RoHS, now prohibiting the use of lead in solder, requires the remanufacturer to
determine which solder has been used because using the wrong material may cause
problems.
The difficulty with regard to reusing electronics, mainly with the semiconductors and the
capacitors, is to assess their age or their remaining life span. However, the remanufacturer
often is aware of the mileage of the car from which a unit has been removed and is in a
position to assess the age of the unit. Not only is the status of the hardware, i.e. the
components, essential, but also the correct software revision embedded in the micro
controllers, is vital for the proper functioning of the reused electronics. The remanufacturer
who has access to the software has the advantage of being able to reprogram the
controllers with the latest software. If the software is not available, simulation or reverse
engineering are the solutions; for further information on this please read, the chapter in this
book, from author Rex Vandenberg.
Reuse Electronics Circuit Boards
Inspection/Evaluation
Circuit Boards Connections Components
Circuit Tracks Substrat Solder Joint Mechanics Housing Function
Passive Active
91
3 The circuit boards
The modern electronic circuit board normally consists of a number of layers supporting the
substrates, the conducting tracks, the through-holes, the solder joints and a varnished
protective coating. In remanufacturing all of these elements must be inspected before the
circuit board is reused.
3.1 Inspecting the substrates
Plastic and ceramic materials are normally used as supporting basis or substrates. During
their operation these substrates may have suffered from chemical or mechanical activity.
A rare chemical damage like corrosion will not allow the board to be reused. Ceramic
substrates are very robust, which practically excludes such damage. The main reasons for
damages are due to mechanical constraints. These can be caused by vibration and
mechanical and temperature shocks. This damage starts as micro-cracks in circuit tracks
and can be difficult to detect in multi-layer boards. If they are significant the boards may
not be reused again. The remanufacturer can cope with this problem by sorting through
more core units then he intends to remanufacture.
Figure 2: Basic construction of a circuit board.
3.2 Inspecting the circuit tracks
The circuit tracks can be damaged by:
• Mechanical constraints on the supporting basis or substrate;
• Chemical corrosion due to salt, solvents and other corrosive substances;
• Humidity; and
• Overload due to higher current or voltages
Mechanical damage was already mentioned earlier, but smaller particles or dirt can also
cause serious mechanical damage, which is however easy to diagnose. Cleaning is
usually the best solution when reusing these boards.
Circuit tracks
Substrate
Surface mounted components
Components in through hole technology
92
Chemical damage will normally show as changes to the surfaces and a visual check will
be an adequate inspection. In such cases the reuse of the board will often be ruled out, but
if the remanufacturer strips more units then he remanufactures, he may be able to cope
with this problem.
Humidity is the next possible damage, but usually the electronic controllers are sealed and
this damage is limited to a low number of units. However humidity can, if very low in
content, be difficult to detect. Humidity generally disappears when the final thermal test is
performed by the remanufacturer. If however the circuit board is already damaged by
humidity it cannot be recovered. Again the solution in remanufacturing is to sort through
more core units than are needed.
Electrical damage resulting from electrical overloads is caused by excessive currents
during the operation of the units, or by electrostatic discharges. These defects can be
repaired by using wire bridges for damaged circuit tracks and by replacing damaged
components with new components.
Figure 3: Cracked solder joints (source: IZM Fraunhofer Institute Berlin).
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4 Inspecting the Connections
Within the connections of the circuit board, mechanical connections and solder
connections are to be distinguished. For many components, the solder connections serve
also as mechanical connections. Larger components often utilise additional screw
attachments. The state of these attachments can be visually inspected. They are normally
without any defect or damage, as damage seldom occurs to these connections. In most
cases, the components can be repaired.
Solder joint failure often occurs because of mechanical tensions resulting from a deformed
circuit board. The solder connections can also be damaged due to poor manufacturing or
wrong solder material resulting in a deterioration of the material structure of the solder
joint. The same defect can also result from undesired foreign solder metals like copper,
gold, cadmium or arsenic. Under certain circumstances, metallic crystals can also be
formed on the surface of the circuit tracks.
During the production of new circuit boards, the inspection of the quality of the soldering is
performed with procedures that are also suitable for inspection during remanufacturing.
The main processes are visual checks of the soldering joints. A camera records figures of
certain areas of the circuit board which clearly show the soldered joints with the help of
image processing. The appearance of the soldered joints is compared with already known
patterns of good and bad, which permits a judgment of the soldered joint. The advantage
of this procedure is the quick and contactless inspection of the soldering joints, without any
damage to the board or the electronic components. Defective soldered joints can be
repaired by re-soldering if the surrounding area of the soldered joints is not too
contaminated by foreign materials. During the repair work it is important to use a solder
with similar qualities to the original one, especially with regard to the aspect of lead- free or
lead-containing. During the resoldering work, the soldered joint and eventually its
semiconductor element will be reheated, which can cause them new damage. The
Remanufacturer needs to take great care in this process.
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5 Inspecting the Components
In order to be reused, the components and the circuit board have to be in a state that
guarantees safe operation during the stipulated second lifetime. Active semiconductor
components are delivered in different case styles and display different levels of sensitivity
to mechanical activity of the circuit board. There is extensive research about failure
mechanisms of the different case types during different levels of stress.
In summary we can say that mechanical stress on the elements is amplified by the rise or
variation of temperature and vibration. Life cycle tests show that periodic stress; especially
low frequencies below 1000 Hz and raised temperatures have negative effects on the
lifetime of the case and the solder connections.
Most of the passive elements like resistors; ceramic capacitors etc. are comparatively
resistant against ageing if they are operated within their specifications. The major
problems concerning ageing of electronic components involve electrolytic capacitors. On
the other hand, their ageing process can be used to determine the approximate age of the
whole circuit board. With time, the electrolyte in the capacitor dries out which causes a
loss of capacitance. On the other hand, by measuring the capacitance of the electrolytic
capacitor an approximate estimation of the age of the capacitor and the circuit board can
be made with the help of a model.
It should however be noted that the ageing state may have been accelerated due to
exceptional temperatures.
95
6 Conclusion
Researching the Internet about circuit board reuse, revealed that the main focus for
different industries seems to be the recycling of electronics to recover metals like gold, or
the extraction of hazardous metals like lead or cadmium. This is indeed a substantial
business but it has nothing to do with the higher level of recycling that the remanufacturers
of this world are achieving. In searching the Internet one can also find companies
recycling semiconductors for sale. There are even attempts to dismantle circuit boards
automatically with robots to recover components. But, I am not aware of who might use
these recycled components, certainly not the APRA automotive remanufacturers! Our
automotive remanufactured units need to be reliable and safe. An automotive vehicle is
after all not a desk computer, a cell phone or an MP 3 player! This report shows clearly the
possible defects of components and how these can be detected. The electronics
remanufacturers are well aware of these potential failures. The reports from Flight
Systems and Injectronics, which can be found in this book, demonstrate clearly that
specialised remanufacturers can reliably handle these.
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97
REMANUFACTURING OF MECHATRONIC AND
ELECTRONIC MODULES FOR TRANSPORTATION VEHICLES- CHALLENGES
AND OPPORTUNITIES
By: Rex Vandenberg, Manager Director of Injectronics Australia
1. Introduction The following article explores different scenarios for remanufacturers, Vehicle
manufacturers, O.E.M suppliers and Tier one Suppliers. These scenarios are used to
explore supply challenges and the solutions available through remanufacturing as well as
the challenges and opportunities for remanufacturers both now and in the future. Scenario One:
You are the manager of a tier - one supplier to a large vehicle manufacturer and you
supply Automotive Electronic components. You have been supplying a certain Electronic
module that has been re-ordered by your customer and you can’t supply it. Your customer
may or may not have purchased the final all time buy from you, but there has been
unprecedented demand for this product of late. There could be a number of reasons you
can’t supply the Electronic Module. These may include:
- one or several microchips or components are obsolete and no longer available.
- Your production line has been dismantled or reset up for new products and it would
be uneconomical to set it up again.
- Your test equipment or assembly equipment is no long serviced or serviceable or is
being used for other products.
- Your production line has had a major setback and won’t be up and running again for
some time.
- The volume requested is so low you are not able to economically produce it, due to
set up cost.
The Question: How are you going to supply your customer?
98
The answer is of course to supply remanufactured units, as a business necessity and an
obligation to our environment. With the sheer volume and variety of automotive electronic
modules, the above supply problems are already common and will only increase in the
future. Many tier one and OEM companies around the world are already using the
services of automotive electronics and mechatronics remanufacturing companies, to fulfill
the supply requirements of their customers. Scenario two
Now imagine you are a traditional remanufacturer. You may already be doing power
steering pumps, power steering racks, automatic transmission units, or Brake calipers.
You are getting an increase in inquiries to remanufacture these units.
However these units now have electronics incorporated, within them, and need to be
tested differently than products you have done in the past.
How are you going to begin remanufacturing these units and keep abreast of the changes,
in the future?
In both scenarios illustrated above, The tier one, O.E.M and traditional remanufacturers
are facing new and ever increasing challenges in their fields.
With more and more electronics and mechatronics utilised within today’s motor vehicles,
remanufacturing is fast becoming an obvious choice to supply these components both
from a financial point of view and very importantly, to minimise the environmental impact.
Engine management systems have evolved in quantum leaps since the early 70’s and the
modern remanufacturer of electronics and mechatronics has needed to keep up with these
developments.
The concept of remanufacturing vehicle electronics and mechatronics components is not
new and companies like Injectronics Australia have been involved in this industry for over
20 years.
As well as engine management systems, there are many other electronic and
mechatronics modules which are being remanufactured. The list includes Engine ECMs,
transmission ECMs, Powertrain control modules, Climate control modules, Cruise control
modules, ABS modules, Air flow and Air mass meters, Dash cluster and other
instrumentation displays, Infotainment, Command centers, radio, Television, Satellite
Navigation, Electronic power steering, Body Control Modules, the list goes on.
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Injectronics Australia has been remanufacturing many of the above components since the
1980’s and provides components and test equipment to other remanufacturing companies
throughout the world including O.E.M and aftermarket companies.
2. Remanufacturing for O.E.M and Vehicle Manufacturers
In past years very few OEM and vehicle manufacturing companies remanufactured vehicle
Mechatronics and electronic components. However, this is increasing considerably with
many OEM and vehicle manufacturing companies forming joint ventures and partnerships
with existing electronic and mechatronics remanufacturing companies.
Some of the reasons an OEM or a vehicle manufacturing company may use the services
of an electronics and Mechatronics Remanufacturing company include:
- Warranty and extended warrant replacement – a vehicle manufacturer may choose
to supply a remanufactured component after a certain time period due to both cost
and environmental benefits.
- Field service campaigns/updates – if an electronic component needs an update or
modification (hardware or software) this task can be performed by an electronics
and mechatronics remanufacturer instead of supplying a new unit.
- Alternative to new – some vehicle manufacturing companies are selling both new
and remanufactured electronic components spare parts, side by side, so the
customer can choose if he wants the more economical, more environmentally
friendly, remanufactured unit. In other cases they may only offer a remanufactured
part.
- Obsolete product replacement - Many OEM or vehicle manufacturers are turning to
electronics and mechatronics remanufacturers as they simply can no longer source
a new electronic module. They may have exhausted their all time buy of this
electronic module and it would be uneconomical to tool up and produce another
short run. It may also be impossible as many electronic components become
obsolete quickly.
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- Going green - An increasing awareness and responsibility towards the environment
is already seeing OEM and vehicle manufacturers reducing their estimations for
total requirements for replacement components during the life of a vehicle. This has
a two fold effect in cost saving and environmental impact because:
a) there is less waste and scrapage of new products when they are not used
and remain as spare parts inventory at the end of the vehicle life.
b) OEM and vehicle manufacturers can turn to remanufacturers if and when
they choose, when the new module becomes a supply issue. They can then
choose the more environmentally friendly approach of remanufacturing.
- Production Line Reworks
There may be times when a product was manufactured with a fault, or a faulty
component or a circuit board loaded incorrectly. In this case a tier one supplier may
choose to utilize the services of an electronics remanufacturer to rectify the fault
before the unit is retested.
3. Remanufacturing Challenges for the Traditional Remanufacturer Automatic Transmissions
For many years, transmissions have been controlled by an Electronic Control Module
(ECM), which has been mounted externally on the transmission unit. However an ever
increasing trend has been to mount the ECM within the transmission itself (see figure 1).
This was done to reduce the amount of connections and wiring around the vehicle. Now
the transmission remanufacturer has to test and validate both the workmanship of the
remanufactured transmission and the function of the ECM. If the transmission is to be
dynamometer tested, there is a requirement to simulate the vehicle signals going to the
transmission ECM the CAN Bus messages need to be simulated and sent to the ECM for
correct operation.
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Figure 1: ECM within the transmission itself.
Electronic Hydraulic Power Steering Pumps EHPS
While testing of the hydraulic function is similar to that of the traditional belt driven pump,
the test equipment has to be able to monitor and supply enough current as well as
command the pump operation. This may be simply switched, or as we have seen lately,
controlled by a CAN Bus message which the test equipment must simulate.
Electronic Power Steering Racks and Columns (EPS)
Electronic Power Steering Pumps are slowly being replaced by full Electronic Power
Steering Racks and Columns (Figure 2). These units have a heavy duty electric motor
that can drive both ways. They also have an electronic control module that takes in the
torque signal as well as CAN Bus messages (such as Roadspeed) from other modules
around the vehicle and in turn drives the Electric Assist Motor. To test these units, the
vehicle CAN Bus and other signals need to be simulated and connected to the ECM.
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Figure 2: Electronic Power Steering Racks and Columns.
In all the above examples the traditional remanufacturer is faced with new challenges.
These challenges include obtaining information and test equipment as well as deciding if
they will remanufacture any electronics in house or externally.
Injectronics Australia has, for many years, been working with O.E.M and aftermarket
electronics remanufacturers, as well as traditional remanufacturers. The services provided
include, test equipment, specialized componentry as well as technical knowledge on how
to remanufacture these products.
One example is the Electronic Power steering tester that will be on Display at the
Automechanika show in Frankfurt.
4. Testing Vehicle Electronics and Mechatronics
One of the essential processes in the remanufacturing of vehicle electronics and
mechatronics, is the ability to fully test all pins and functions of a module. This testing may
be required both prior to and after the remanufacturing process.
As this equipment is not readily obtainable, electronics and mechatronics remanufacturing
companies have needed to design and manufacture their own.
Injectronics Australia has for several years used their own designed and manufactured
tester, called a Virtual Automotive Simulator (V.A.S.). (See figure 3) The V.A.S. involves
an interface between a Personal Computer and an electronic component under test.
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Figure 3: Virtual Automotive Simulator.
The V.A.S essentially operates and drives the electronic module to be tested by simulating
and stimulating the inputs and monitoring the outputs and compares these measured test
results to previously recorded results of a known good unit.
The Injectronics Virtual Automotive Simulator or V.A.S. has three levels of operation which
are password protected.
Level 1: This level enables a worker of any skill level to simply log in, connect and test. At
the end of the test a software report is generated and electronically stored and an optional
printed report can be produced.
Level 2: This level of operation is designed for the Technician who may want to analyze a
particular circuit function for diagnostic purposes. The technician can adjust and vary the
inputs and monitor for the expected responses.
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Level 3: This level is for the Software Programmer who writes a test script. The test script
uses a multitude of pre written call up menus, macros and blocks that the programmer can
join together to write a test script quickly.
An essential piece of test equipment for the remanufacturing of air flow and air mass
meters is an air meter analyser. An air meter analyser needs to be able to quickly and
accurately learn and store the flow characteristics of a reference unit. Then, it must be able
to automatically and accurately test the full output range by varying the air flow of a
remanufactured air flow meter for a small four cylinder engine through to air flow meters
that suit a large V8 engine. There are different air flow load outputs such as varying
voltage or varying frequencies. As this test equipment is not available on the open market,
Injectronics has designed and built its own Air Meter Analyzer (AMA) to test air mass
meter brands such as Hitachi, Jecs, Bosch, Siemens, Mitsubishi and Kefico. (See Figure
4)
Figure 4: Test bench for air flow meter.
5. Identifying Electronic Components
If a remanufacturer does not have access to specific circuit board and component
information, they may need to reverse engineer the assembly. Most electronic
components have identification markings but relevant information may still be unobtainable
for the component.
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With reverse engineering, there is the possibility of determining and sourcing a
replacement component or a component that has a higher rating to ensure that it does not
fail again.
6. Obsolete Components - Obtaining Components
Another challenge for our industry is obtaining components to enable the repair of
electronic and mechanical parts. For components that are not replaced in every
remanufacturing process, it may be possible to take components from another core if it
can’t be obtained new. However in many cases one or several components may be
replaced in each ECM. The reason is because, for that unit, it has been found over a
period of time that certain components are troublesome and if they have not already failed,
they may fail in the future. Replacing all possible troublesome components, of course,
reduces possible warranty returns and unsatisfied customers.
After the challenges of identification, the next challenge is to source the components.
Standard components such as transistor drivers and common IC’s can usually be obtained
from electronic component part suppliers. Another challenge for our industry is that IC chip
manufacturers are often now producing custom components for ECM manufacturers.
These components cannot be obtained through the aftermarket channels. In other cases
by the time there is a demand for an ECM to be remanufactured, which could be 5 years
after it was manufactured, the actual IC-chip component has long since finished it’s
production run and is now obsolete.
Even if a component is identifiable and information is available, it is still possible that the
electronic component itself cannot be obtained. In these cases there are a number of
options including:
a) acquiring from donor boards – there may be excess new or second hand
modules which are not necessarily the same as what needs to be remanufactured
but have the same required electronic component which can be removed and used.
b) Component brokers. There is a large industry of electronic component brokers
who source electronic components from around the world. These components may
be obsolete but are no longer required by circuit board manufacturers or stocked by
their manufacturers.
c) Design and produce – in many instances an electronic component cannot be
obtained and so Injectronics has needed to design and produce an electronic
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component so that an electronic or mechatronics module can be remanufactured.
The Research and Development department at Injectronics has had many years of
experience at reverse engineering and designing totally new replacement
components. Some examples are shown.
Figure 5: I/0 Buffer, watchdog circuit and voltage reference module.
This 40 pin component (Figure 5) is found in many European vehicles including Volvo,
Saab, and Porsche. The original component is made on a ceramic board, however
Injectronics has manufactured a replacement board and because size was not an issue it
was made as a single sided board within the module.
Figure 6: 44 pin programmable expansion chip.
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This IC (Figure 6) was used in many Mitsubishi vehicles. Information of this component
was not available so Injectronics reverse engineered it and identified its functions.
Injectronics then sourced a 64 pin component which was physically smaller, so it could be
mounted on a sub board and tracks routed to the correct pins. It then was programmed to
operate in the exact same manner as the original chip.
Figure 7: Intelligent ignition driver.
The original circuit board (bottom figure 7) controls the ignition drivers in a Mercedes Benz
vehicle and provides feedback to the microprocessor such as burn time.
The 2 sided circuit board (top figure 7) was designed by Injectronics and is also mounted
on a cast aluminum retaining bracket.
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7. Quality of Remanufactured Electronics and Mechatronics
The question is often asked “How does the quality of a remanufactured electronic
component compare to that of a new part?”
Many reputable electronics and mechatronics remanufacturing companies have developed
a reputation for their exceptional quality over many years. There are some that have
obtained a Quality Certification such as ISO9001:2000 like Injectronics.
In many cases, most products are close to, or have a lower warranty fail rate than that of
the new equivalent. By developing stringent test programs, and remanufacturing
processes and continually reviewing production and warranty claims, the warranty failures
can easily be maintained at a minimum. Wherever possible, modules are remanufactured
with electronic components that have higher specifications, or reprogrammed with the
latest software, making them even more reliable than a new, non remanufactured unit.
8. Designing a Test Program
As there are many variations of electronic and mechatronics modules used in vehicles, a
specific testing and remanufacturing process needs to be designed for each module. In
many cases, the module can be communicated with by the serial data line/CAN Bus.
Numerous amounts of information can be obtained via the serial data stream such as part
number, hardware version, software version; variant coding, fault codes, as well as serial
read back information on many inputs and outputs.
If testing specification or serial data information is not available from the manufacturer,
then Injectronics would need to reverse engineer the module to determine each pin
function to be able to determine an exact specification. The correct output loads also need
to be connected during the test cycle. All these factors are considered when setting
tolerances. Injectronics has more than two decades of experience simulating signals such
as Crankshaft, Camshaft, serial data - CAN Bus, as well as setting the tolerances and
developing test programs.
Many different tests may need to be performed on just one pin.
109
An example of some of the points tested in a current controlled Injector wave-form is seen
in Figure 8 below.
Parameters tested are:
A) static voltage
B) minimum voltage
C) amplitude of pre switching spike
D) amplitude of post switching spike
E) Injection start time (phase)
F) initial pull on time
G) injection duration
H) switching/current control frequency
Figure 7: Example of some of the points tested in a current controlled Injector wave-form.
In setting up the calibration points and specification, a known good unit or new reference
unit is connected to the VAS tester and stimulated and driven through the various test
sequences. During this time the calibration points are learned and stored and then
referenced against when testing subsequent units. The test sequence may also require a
vibration test and a controlled temperature variation test (cold to hot, hot to cold).
110
9. Costing Remanufactured Modules
The cost of remanufacturing a vehicle electronic or mechatronics module can vary
depending on many factors including:
1) Quantity of units to armortize setup costs against
2) Repairability – how difficult to dismantle
3) Core – costs and availability
4) Component availability – Can components be obtained or do they need to be designed.
5) Level of technology – is it a 10 pin electronic module with limited functions or a 200 pin
sophisticated device which required a lot more time to develop a test.
6) Writeoff ratio –Within a batch of cores there may be some units that cannot be
remanufactured, such as water damaged units, or burnt circuit boards
7) Information availability – Will the customer supply all the specifications and CAN Bus
information or does the remanufacturer need to determine.
As a result of the above variations the price of remanufacturing a module can vary
between one tenth to two thirds that of a new component.
- When Injectronics is engaged to assess the suitability of remanufacturing a module,
we will confer with the customer and discuss the above points. A project plan is
then developed, that is tailored to the module and the customer so Injectronics can
work toward a final costing.
10. Conclusion
Electronic and mechatronic remanufacturing companies have been remanufacturing for
many years with exceptional results. There is an ever increasing use of these types of
modules, for many different functions, in many different transportation vehicles.
Additionally there is an increasing demand to minimize inventories and provide sustainable
and environmentally friendly products. As a result the OEM and Vehicle Manufacturer and
the traditional remanufacturer are joining with electronic and mechatronic remanufacturing
companies to provide the necessary solutions.
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REMANUFACTURING ELECTRONIC CONTROL MODULES –
EVOLUTION IN PROGRESS
By Joseph W. Kripli, President, Flight Systems Electronics Group
Flight Systems Electronics Group manufactures and remanufactures electronic control
modules for a wide variety of customers and products. Flight Systems Electronics Group
started in 1968 producing solid state relays for NASA for the Moon Rover program and
eventually evolved from forklift control modules into automotive and heavy duty truck
modules.
Figure 1: Group shot of Diesel electronics system.
112
The first process in remanufacturing begins with the “Core”. The core is the failed unit from
the vehicle from which the failure occurred. The failure is typically an engine warning light
on the instrument cluster or worst case, an engine “no start” condition.
The failure is confirmed by connecting the appropriate scan tool in order to identify the
fault code which is kept in the memory of the electronic control module. The fault code is
then identified through the manufacturer’s repair manual and identified as a failed engine
control module and instructed to be replaced. Typically, the manufacturer will begin their
core program by using new electronic control modules as seed stock and place them into
a product box identified as remanufactured and put in place a “core charge” which is a
billing method to ensure that the failed module is returned to begin the method of core
collection. Ideally, you would begin a remanufacturing program with a core quantity equal
to one year of unit sales.
Now that we have a product to remanufacture, we are ready to begin the process of
identifying and sorting core. Due to the fact that the core is a failed unit that has been on a
vehicle for a number of years, it is most likely that the core is not the latest part number
and that there has been a number of revisions over the life of the vehicle application. The
goal is to produce a product with the latest hardware and software revisions as to supply
the customer with the best quality product. By identifying and sorting the core, we can
establish at what change level our inventory of cores is at. After the identification process,
we can begin ordering components as we now understand what is required to upgrade the
core to the latest revision. We do not yet know what component has failed thus causing
the “check engine light” to go on. Some remanufacturers suggest pre-testing the unit, I find
that if you are going to upgrade the unit to the latest revision level, then chances are you
are going to have to change components anyway and therefore the process is leaner to
just repair and upgrade the unit at the same time and remove this step.
With the core process complete, we are ready to begin disassembly and cleaning of the
unit. We refer to this as “core prep”. Core prep consists of removing the covers and
protecting the connectors in order not to damage them in your own cleaning process thus
increasing your product cost. Also at this time, it is important to identify what the unit part
number will be as a finished unit. A tagging process is suggested. The process to clean
the core is typically simple with such equipment as sand blasters and a machine we refer
to as a “slurry” which is a sand and water mixture which gives an excellent finish to
aluminum housings.
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Figure 2: Chrysler JTEC (Jeep/Truck Electronic Controller).
I find that the plastic housings are best cleaned with a water soluable cleaning solution that
is biodegradable. Again, some remanufacturers will suggest testing prior to the cleaning
process due to the “red tag” failure. Red tags will occur if the unit was damaged in a fire or
collision, and if it experienced a catastrophic board failure. I believe you will sort that
during the cleaning process and remove 99% of the damaged product without testing as
an experienced cleaning person will recognize damaged units and black burnt sections of
PCB boards.
Now we are ready for our first test. It is the firm belief of Flight Systems Electronics Group
that 100% of units are tri-temperature tested. These test temperatures are normally minus
40 degrees Celsius, plus 125 degrees Celsius and ambient temperature. This requirement
assists with the finding of intermittent failures occurring in temperature related regions
throughout the world. We get limited or no information about the failed unit, so we do not
know if the failure was only occurring in the morning or after warm-up of the engine.
I normally test hot first (plus 125 degrees Celsius) due to the fact that some units have
been cleaned with water and this removes any remnants of moisture prior to connecting
the tester. The tester is your most important capital equipment you have in the
remanufacturing process. Ideally you would receive an end of line tester from your
customer or the original equipment manufacturer. It is possible to create or reverse
engineer your own; however, this is an extremely difficult and time consuming process.
Also, due to the different variations of modules, it can become a very large capital
investment. So the first test is hot and we separate the failures from the passed units. The
114
failed units are now sent to the technicians who will troubleshoot the unit and determine
the failure. Also at this time, the technician will upgrade the unit to the latest hardware
level. After repair and upgrade, or after the unit passes the “hot” test, we move on to the
cold test.
The cold test requires a set time to achieve the temperature of minus 40 degrees Celsius.
The unit is then tested again on the same tester and again sorted by failure and passed
test criteria. Should the unit require repair, then the technician will troubleshoot the unit
and likewise upgrade to the latest hardware level. Keep in mind that you must repeat the
hot test after you change any parts which failed the cold test. At this point, if the unit
requires upgrading, it will now move to the technician and repeat the hot and cold test.
This may not appear as a lean process to many people; however, the data acquired from
the testing is vital to understanding the typical failure modes of electronic control modules
in order to establish a common repair group which assists in component ordering and
troubleshooting techniques. With this established it will assist you in your core sorting and
improve your core purchasing.
Figure 3: Soldering 128 pin Microprocessor.
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During the technician repair process, you will come across some units with what is referred
to as “potting”, a silicon/rubber type composite used for vibration and weather protection or
the components will be covered with conformal coating which is a thin coating protecting
the components from erosion caused by humidity. At times, the potting material can be
difficult to remove and work around. Processes must be developed to remove these
coatings thus allowing the technician access to the failed component. We must reinstall
the same OEM potting/conformal coating material to bring the unit back to its original
conformity. After the potting is reinstalled we are now ready for final testing at ambient
temperature. At this test, the electronic control module receives its software specified for
the vehicle application. Some electronic control modules will use a generic software and
the exact specifications will be “flashed” into the module at the dealership following
installation utilizing the Vehicle Identification Number to properly link and install the correct
software provided by the OEM with the correct vehicle. Should the electronic control
module fail this test, it must be repaired and begin the tri-temperature testing process
again to ensure that a high level of quality is maintained.
Figure 4: Instrument Cluster PCB Board.
116
The passed unit is now ready for packaging and shipment to the customer. Ideally you
want these units to be serialized and dated for tracking capabilities. The unit should be
wrapped in an anti-static paper or bubble wrap to ensure that no electro static discharge
occurs when handling the unit. It should also be mentioned that ESD protection is used by
the technicians and people testing the units throughout the process.
Although the average vehicle averages 16 modules per vehicle today, we are not always
capable nor is it always cost effective to remanufacture the unit. For example, if the unit
cost is below $50 USD, then it may not be cost effective to process this unit through the
rigorous remanufacturing process. Instead, it may be more cost effective to produce a low
volume new build run of this electronic control module. An example would possibly be a
heated seat module or a headlight module that has limited microprocessor technology
within the unit, and a low failure rate in the field.
Figure 5: Chrysler SBEC1 (Single Board Electronic Controller).
Remanufacturing without a doubt reduces the impact of electronic control modules on
waste landfills, thus causing a “green” effect in the electronic control modules cycle of life.
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Another avenue for remanufactured electronics is certain applications referred to as
“Mechatronics” which utilize a percentage of mechanical components and a percentage of
electronic components. An example is GM 6’5 Liter Diesel Fuel Injection Pump required to
meet certain vehicle emission levels which utilizes this split in componentry. Diesel Fuel
Injection Pumps require the assistance of electronic components to assist in timing which
in turn effects the combustion process. This precise timing allows for better management
of the emission related gases that are exhausted from a diesel engine.
Figure 6: GM 6.5 Liter Diesel Fuel Injection Pump.
By taking the expertise we have gained from the electronics remanufacturing programs
and meshing with the mechanical knowledge established over the last 40 years, we
develop an ability to approach a different market from where the mechanical
remanufacturers have not afforded themselves the expertise at this point in time to
overcome the failure mode understood by the electronic control module technician. Thus
“Mechatronics”. Thus the “Mechatronic Technician” is born.
118
119
Authors of the book:
Joe Kripli
President
Flight Systems Electronics Group
Ph: +1 717-932-7000 x527
Fax:717-932-7001
E-mail: [email protected]
Rex Vandenberg
Managing Director
Injectronics Australia Pty Ltd
Ph: +613 8792 6999
Fax +613 8795 7205
E-mail: [email protected]
Prof. Rolf Steinhilper
University Bayreuth
Ph: +49 921-55-7300
Fax: +49 921-55-7305
E-mail: [email protected]
Dr. Stefan Freiberger
University Bayreuth; Fraunhofer Project Group Process Innovation
Ph: +49 921-55-7324
Fax: +49 921-55-7305
E-mail: [email protected]
Fernand Weiland
FJW Consulting
Ph: +49 2203 25577
Fax: +49 2203 292984
E-mail: [email protected]
120
Associations, Institutes & News Magazines links:
APRA USA
Automotive Parts Remanufacturers Association
William C. Gager, President
Ph: 703-968-2772 ext 103
Fax: 703-968-2878
E-mail: [email protected]
www.apra.org
APRA Europe
Fernand Weiland
Ph: +49 2203 25577
Fax: +49 2203 292984
E-mail: Fernand:[email protected]
APRA Europe - Webmaster & Communication
Gregor Schlingschroeder
Ph: +49 2863 92 444 11
Fax: +49 2863 92 444 21
E-mail: [email protected]
APRA Electronics & Mechatronics Division
www.apra-europe.org click “mechatronic division”
Board members:
Ron Carr; [email protected]
Joe Kripli; [email protected]
Aron Regev; [email protected]
Rolf Steinhilper; [email protected]
Jeffrey Stukenborg; [email protected]
Fernand Weiland; [email protected]
ReMaTec News
Luuk Aleva
RAI Publishing House
tel. +31 (0)20 504 28 00
fax +31 (0)20 504 28 88
E-mail: [email protected]
121
Rochester Institute of Technology
National Center for Remanufacturing and Resource Recovery
Rochester, NY 14623 (USA)
Robert German [[email protected]]
Nabil Nasr [[email protected]]
University Bayreuth
Bayreuth (Germany)
Ph: +49 921-55-7324
Fax: +49 921-55-7305
E-Mail: [email protected]
Remanufacturers of Automotive Electronics
Flight Systems Electronics Group
Ph: +1 717-932-7000 x527
Fax +1 717-932-7001
E-mail: [email protected]
Flight Sytems Europe
Bodo Ruthenberg
Ph. +49 89 124 76 187
Fx. +49 89 124 76 189
E-mail: [email protected]
Injectronics Australia Pty Ltd
Ph: +613 8792 6999
Fax +613 8795 7205
E-mail: [email protected]
Hitzing & Paetzold
Gladbeck / Germany
Tel +49 (0) 2043 94 44 49
Fax +49 (0) 2043 94 44 50
E-mail: [email protected]
122
BBA-reman UK
Chris Swan
Ph: +44 7967 00 1579
E-mail: [email protected]
Delphi Product & Service Solutions
Troy MI (USA)
Jeffrey S. Stukenborg
Ph: +1 248-267-8746
Fax: +1 248-267-8877
E-mail: [email protected]
Robert Bosch GmbH
Automotive Aftermarket
Karlsruhe (Germany)
Ph. +49 721 942-2741
Blue Streak Europe
Standard Motors Ltd
Ph: +44 1623 886400
Fax: +44 1623 751761
E-mail: [email protected]
Blue Streak Canada
Ph: +1 905 669 4812
Fax: +1 905 669 5179
E-mail: [email protected]
Actronics - Netherlands
Leon Kleine Staarman
Ph: +31-546-660418
Fax: +31-546-660419
E-mail: [email protected]
To order this book pleases contact:
For Europe: www.apra-europe.org
For all other countries: www.apra.org
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