ELECTRICAL REBUILDER’S ASSOCIATION — Auto Electric Corner 2019_08 www.electricalrebuilders.org

An ERA Publication. ©2019, Electrical Rebuilder’s Association. All rights reserved. No portion of the guide may be reproduced in any way, or stored in any electronic retrieval system without the prior written consent of the Electrical Rebuilder’s Association.

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8442 Alternator ord 8442 and similar ones like the 8403 and such have been the subject of a few calls on the Help-Line, thus I will try to shed some light on issues involving the operation of this alternator. It was installed on certain models of the Ford Escape, Mazda Tribute and Mercury Mariner trucks (SUV), as well as Mercury Montego and Ford Five Hundred cars of 2004 to 2008, all with 3.0L engines. It is a 4-G, 130-Amp PCM driven unit with the typical A-Sig-Fr pins on the regulator. �is regulator, if OE, can be identi�ed by its white color. Most a�ermarket versions use the same white color for the regulator but there are exceptions. For instance, Taditel's replacement for this regulator (T-816) is black in color like the rest of their regulators (see Figure 1). What makes a distinction between the part numbers is that 8403 has through-bolt extensions to allow the installation of a plastic shield, but 8442 does not have the through-bolt extension as its cover shield wraps around it and is secured in place with the alternator mounting bolts (see Figure 2). �e R&R of this alternator is labor intensive and in some models requires the removal of the right drive-sha� for access. As in most such cases with di�cult installation and �ghting tight spaces, some (if not most) technicians will discard the shield which leaves the alternator a little less protected, but usually what end- user does to a unit is not discussed until something goes wrong. I have no data to show whether discarding the shield contributes to the longevity (or lack thereof) of this unit, but experience has shown the OE doesn’t go through the expense of installing a shield around their alternator unless they are aware of some bene�ts. Occasional calls on ERA Help-Line are inquiries regarding testing this alternator. When asked if the caller has any appropriate test box, the answer is usually NO…! To which the only response I have is that you cannot test that alternator properly if you do not have the right test box and are familiar with its features. In the case of the alternators mentioned above, you realize how important it is to make absolutely sure your unit is tested thoroughly. Otherwise you could be subject to a warranty return and perhaps anywhere between �ve to eight hours of labor claim. Like any other unit with labor-intensive installation, the quality of the reman unit must be high and a detailed testing of the unit is of utmost importance. Being a Ford PCM-driven alternator, it must be checked using the appropriate test box. Fortunately a variety of those are readily available to rebuilders. A recent Help-Line call about the above alternator was regarding the lack of voltage setting response that

the rebuilder was getting from a Jimco’s TB-88 test box. Asking Juan Grube about it, I learned that TB-88 was made in 1999, which is 20 years ago! Certainly the electronics of the regulator have changed since then due to changes in system designs and availability of more sensitive and faster responding chips. �us the new and more capable version of this test box, the Jimco TB-337 (see Figure 3), has much better duty cycle control and

Modern Starting Circuits & Hitachi Motor-Alternator BY MOHAMMAD SAMII

AUTO ELECTRIC CORNER — Testing PCM Ford,

F

Figure 2 – Splash shield for the 8442 alternator.

Figure 1 – 8442 and/or 8403 alternator.

ELECTRICAL REBUILDER’S ASSOCIATION — Auto Electric Corner 2019_08 www.electricalrebuilders.org

An ERA Publication. ©2019, Electrical Rebuilder’s Association. All rights reserved. No portion of the guide may be reproduced in any way, or stored in any electronic retrieval system without the prior written consent of the Electrical Rebuilder’s Association.

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sharper square waves that can be easily seen on a scope, for those of you who have the time, patience, AND the scope to play with in your spare time! �e bottom line is whatever test box you use, you need to verify that your alternator is functioning properly before it goes on the car. One Help-Line call regarding this alternator that we �nally �gured out was that the rebuilder was using a non-PCM regulator, and that was the reason the warning light on the dash would not go o�…! I have personally repaired few of such troubled vehicles when the wiring from PCM to the alternator was damaged and in one case the PCM itself needed to be changed to get the alternator to charge properly. Any issue with the PCM-to-alternator communication makes the alternator go into its default mode of 13.5 V. It will appear to be charging �ne but leave a glowing BAT light on the cluster.

2015 starting system F-250 In a thread of discussion on the website, the question regarding starter engagement and �ywheel damage issues on a 2015 Ford truck with Turbo–Diesel arose that was answered with di�erent responses. Some even assumed that perhaps the culprit could have been an ignition switch with a pitted contact that was not supply enough power to the starter “S” terminal, thus causing occasional interrupted-engagement and the reason for milling and �ywheel damage. �at question prompted me to explain the modern starting system in newer vehicles that is far from the assumption we had as how the things worked in the past. If you look at the block-diagram for a 2015 Ford truck (see Figure 4), you will see how much things have changed. �at is to say the design and the starting sequence of the starting system is now a lot less dependent on the ignition switch, involving a lot more other modules that all need to work and communicate properly to make the starter to crank. As you can see in the diagram, the ignition switch merely applies a very low voltage signal to the BCM (usually 5V), requesting a start…that’s all. �e

BCM proofs the anti-the� system, making sure that it is the right key in the switch (or the proper key FOB in driver’s possession in the case of push-to-start button), and relays the message to PCM. Meanwhile the TCM (Transmission Control Module) is also involved sending the right information indicating if gearshi� lever is in park position. �en, and only then, if all the information seems correct, the will PCM activate the starter relay and that relay applies power to the “S” terminal of the starter. Some of that information between the modules is hard-wired, but a good portion of it travels through the vehicles communication system such as the CAN bus. So you see, the ignition switch only applies a request for the start and once the information is received by BCM, the ignition switch is practically out of the loop. �erefore the condition of its contacts do not have any bearing on the starter's engagement or crank duration.

BAS, Mild Hybrid,…and Stop/Start �e Stop/Start systems are appearing more and more on the market. �ey fall into di�erent types and versions and some of them are subject of an occasional call on the Help-Line. �ey are a lot more prevalent in the European market, but most manufacturers are now o�ering them in US market as well, and their numbers are increasing, so you may occasionally run into one. An early or even the earliest production version in our market was used in the “Green Line” series of the Saturn Vue Hybrid from 2007 until the late 2009 when GM eliminated the Saturn brand. �ese cars that were classi�ed as mild Hybrid and used an 11469 Hitachi- built combo starter/alternator that GM called its BAS, for Belt-Alternator-Starter with a GM Part# 23245892, 24242950, 24243969, and a few others (see Figure 5). As the name implies, this is a belt-driven unit that works as an alternator and also as an AC motor. When

AUTO ELECTRIC CORNER

Figure 3 – Jimco’s TB-337 Test Box for Ford PCM alternator.

Figure 4 – A simpli�ed 2015 Ford F-250 starting system block diagram.

ELECTRICAL REBUILDER’S ASSOCIATION — Auto Electric Corner 2019_08 www.electricalrebuilders.org

An ERA Publication. ©2019, Electrical Rebuilder’s Association. All rights reserved. No portion of the guide may be reproduced in any way, or stored in any electronic retrieval system without the prior written consent of the Electrical Rebuilder’s Association.

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Figure 5 – GM’s BAS 11469 Motor-Generator for Saturn Vue hybrid.

AUTO ELECTRIC CORNER

the proper power was applied to it, it would crank the engine. It is also able to mildly assist the vehicle’s 2.4L Ecotec engine when extra power was required as in cases of acceleration for passing. �is assist feature is not available on Stop/Start systems that use a traditional starter and alternator as most new cars do. �e BAS Motor-Generator has 3 blue high voltage lines for its 3-phase operation (see Figure 6). �e 3-phase output is recti�ed by an external BGCM (Battery Generator Control Module) to charge a 36V NIMH (Nickel Metal Hydride) battery at 42 Volts. It also supplies 12V for the accessories, as well as managing the entire power production. In starting phase, the module would convert the 36V DC into a 3-Phase AC, and apply it accordingly with proper sequence to the unit, depending on the position of a full-�elded rotor in relation to each stator phase. Its cranking operation is very so� and smooth. When I am asked by callers if this unit can be tested and repaired, my answer is usually an emphatic NO…! To the best of my knowledge, as it stands right now, we rebuilders do not have the capability for doing anything to this unit with the exception of changing the bearings. As I see it, we do not have access to any service parts, rebuilding instructions, skills or any appropriate test equipment to rebuild or repair this unit. In my opinion, you can make more money if you say NO to the customer who requests that you check and repair it…! Having said so, since I have one of these units, I am planning by use of an external recti�er and 3 batteries to make a 36V battery bank, �nd a way to apply gradually the �eld current to at least check the alternator function of the unit. I will let you know if the process was successful. Well, that’s all for this issue. Until I see you again, keep up the good work.

You can contact Mohammad Samii by email at: sammyselectric@sbcglobal.net, or call him on the ERA Tech Help Line at: 636-584-8324.

Figure 6 – �e output wires connection to the GBCM.