Brake & Front End

®

A

� Control Arm Replacement � Spotting California Converters � TPMS Corrosion Issues

May 2013BrakeandFrontEnd.comMAGAZINE

Reader Service: Go to www.bfeRAPIDRESPONSE.com

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28ABS ServiceHow software is changing braking.Changes in brake technology used tobe hardware based. Today, electron-ics are driving most of the advance-ments in braking technology.

36Control ArmsWhy do they wear out?Ball and socket joints, like ball joints,tie rods and sway bar links, wear out.To properly inspect these joints forwear, you must use you hands andeyes.

58Wheel Bearing & Wheel Speed SensorsReplacing a wheel bearing involves dealing with a wheel speed sensor.The average wheel bearing job may require a scan tool, scope or ameter to verify the operation of the wheel speed sensor.

PublisherJim Merle, ext. 280 email: [email protected]

EditorAndrew Markel, ext. 296email: [email protected]

Managing Editor Tim Fritz, ext. 218email: [email protected]

Technical Editor Larry Carley

Graphic Designer Dan Brennan, ext. 283email: [email protected]

Ad Services DirectorCindy Ott, ext. 209email: [email protected]

Circulation Manager Pat Robinson, ext. 276email: [email protected]

TECH FEATURE: ABS Function

CONTENTS

A Publication

Sales Representatives:

Bobbie [email protected], ext. 238

Doug [email protected] 330-670-1234, ext. 255

Sean [email protected], ext. 206

Dean Martin [email protected] 330-670-1234, ext. 225

Glenn [email protected] 330-670-1234, ext. 212

John Zick [email protected] 949-756-8835

List Sales Manager

Don [email protected], ext. 286

Classified Sales

Tom [email protected], ext. 224

ADVERTISING REPRESENTATIVES

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PRESIDENT

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VICE PRESIDENT

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BRAKE & FRONT END (ISSN 0193-726X)(May 2013, Volume 85, Number 5): Published monthly by Babcox Media, 3550 Embassy Parkway, Akron, OH 44333 U.S.A. Phone (330) 670-1234, FAX (330) 670-0874. Periodicalpostage paid at Akron, OH 44333 and additional mailing offices. POSTMASTER: Send address changes to BRAKE & FRONT END, P.O. Box 13260, Akron, OH 44334-3913. BRAKE &FRONT END is a trademark of Babcox Publications, Inc. registered with the U.S. Patent and Trademark office. All rights reserved.A limited number of complimentary subscriptions are available to individuals who meet the qualification requirements. Call (330) 670-1234, Ext. 260, to speak to a subscription servicesrepresentative or FAX us at (330) 670-5335. Paid Subscriptions are available for non-qualified subscribers at the following rates: U.S.: $69 for one year. Canada: $89 for one year.Canadian rates include GST. Ohio residents add current county sales tax. Other foreign rates/via air mail: $129 for one year. Payable in advance in U.S. funds. Mail payment to BRAKE& FRONT END, P.O. Box 75692, Cleveland, OH 44101-4755. VISA, MasterCard or American Express accepted.

6 Viewpoint

8 ASE Test Tip

12 Brake Lights

14 Industry Review

20 Gonzo’s Toolbox

24 Alignment Specs

34 Tool Cool: Caliper Gauges

42 Brake Pulsation

48 TPMS Sensor Corrosion

52 Catalytic Converters

64 Parasitic Draw

66 Tech Tips

72 Product Showcase

75 RAPID RESPONSE

76 Classifieds

80 Brake Job Pointers

Brake and Front End is a member of and supports the following organizations:

DEPARTMENTSColumns

AUGMENTED REALITY CONTENT IN THIS ISSUE:

Auto-Video Inc. 53, 63TPMS Sensor Corrosion 48Catalytic Converter Replacement 52

4 May 2013 | BrakeandFrontEnd.com

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48

52

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In: Being able to re-flash andcalibrate computer modules.

Out: Longer than normaltime downloading a filebecause someone is watchingNetflix in the front office.

In: Calling yourself amechanic.

Out: Everyone calling him-self or herself a technician.

In: Not leaving the bay byusing your smartphone ortablet to look something up.

Out: Realizing that youneed your “cheater” glasses toread it.

In: ABS, ESC and tractioncontrol preventing major acci-dents.Out: ABS and traction control

preventing you from doing awicked burnout or donut.

In: Being able to rebuild acaliper.Out: Scratching the bore

with a screwdriver trying toinstall the piston seal.

In: Buying Google AdWordfor mobile to attract new cus-tomers.Out: Dealing with a

Facebook page for your shop.

In: Getting control of yourYelp profile.

Out: Realizing all thereviews are from your bestbuddy and are poorly written.

In: Doing your own land-scaping to improve the look ofyour shop.

Out: Realizing that com-pressed air does not make agood gardening tool way toolate.

In: Wearing safety glasses.Out: Trying to find a pair

that does not look too dorky.

In: Buying a grill for the shopso your staff can enjoy a goodburger or hot dog for lunch.

Out: Having to clean it.

In: Selling scrap metal formoney.Out: Scary scrap collectors

scaring away your customers.

In: Having the right TPMSservice kit in stock.Out: Breaking a stem

because it is corroded.

In: Talking to a countermanthat understands what otherparts might need to be replaced.Out: Customers bring in parts

they bought on the Internet.

In: Using Motorist AssuranceProgram (MAP)(www.motorist.org) practicesand standards for communicat-ing with the customer.Out: Trying to sell a cus-

tomer muffler bearings.

In: Using a waste oil burnerto keep your shop warm in thewinter.Out: Running out of waste

oil on the coldest day of theyear.

In: Customers who take careof their vehicles.

Out: People who sell theircar because they are afraid inmight break down on them.Out: OEMs that feed this

trend to increase sales.

In: Finding a good fleet cus-tomer. Out: Used car dealers who

want the least work done forthe lowest price.

In: Tool truck drivers that areconsistent.

Out: Tool truck drivers whodrink your coffee and are neverabout to warrantee tools.

In: Training.Out: Send cars to the

dealer. �

Here is my list of what is “in and out” this month

Viewpoint By Andrew Markel | Editor

If you have your own, please send them to me at [email protected].

ASE A5 Quick Tip

Brought to You By AVI & Brake & Front End

If you took the ASE A5 test afew years ago and are retakingthe test this year, there have

been a few changes. The mostdramatic changes are in section Fof the required task list for elec-tronic brake control. The sectioncomprises seven question andcounts towards 17% of your score.

HERE IS THE NEW STUFF• Diagnose electronic brake con-

trol system, electronic control(s),components, and circuits usingon-board diagnosis and/or recom-mended test equipment; deter-mine needed repairs.

• Remove and install electronicbrake control system componentsfollowing manufacturers’ proce-dures and specifications; observeproper placement of componentsand routing of wiring harness.

• Test, diagnose and service elec-tronic brake control system sen-sors (such as speed, yaw, steeringangle, brake pedal position, etc.)and circuits following manufac-turers’ recommended procedures(includes output signal, resistance,shorts to voltage/ground, and fre-quency data).In a nutshell, they want you to be

able to service and understand theoperational theory behindElectronic Stability Control (ESC)systems. This includes how the sen-sors operate and the serial databuses they use to share information. In previous tests, scan tool usage

was only vaguely discussed. Thisyear, the test will discuss how tolook at senor data from wheel-speed sensors, steering angle andyaw/accelerometers. While the

test is tool brand neutral, knowthe basic theory of how the scantool can monitor the brake systemand bi-directionally control thesystem for testing and bleeding.

Also, brush up on reflashing,recalibrating and reprogrammingmodules and sensors. There issure to be a question on the testthis year about “technician A”replacing a part and “technicianB” saying it is defective.

Also, brush up on your activewheel-speed sensor diagnostics.You need to know that these sen-sor produce a square wave andhow they differ from passive sen-sors. Also, you need to knowwhat type of resistance test workswith what sensor.

LIST OF ARTICLES THATCAN HELP YOU PASS THEA5:• Wheel-Speed Sensor Diagnostic:

Meter and Scope Methods, Brake &

Front End, September 2012, page 48;• Steering Angles Sensor

Diagnostics, Brake & Front End, July2012, page 40;• ABS HCU Diagnostics, Brake &

Front End, October 2012, page 12;• Re-Flashing Repairs, Brake &

Front End, October 2012, page 60;• Wheel Bearing Hub Q&A, Brake

& Front End, March 2013, page 36;• ABS Solenoid Diagnostics, Brake

& Front End, April 2013, page 30;and• Diagnosis of Accelerometers &

Yaw Sensors, Brake & Front End,April 2013, page 22. �


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Brake Lights


“A customer came in and said the brakes were makingnoise, and then stopped all of the sudden, we found this.”–

Kyle Peterson-Sears Automotive, Grand Junction Colorado


Do you have your own bad

brakes story and pictures? If

you do, it could be worth $75

and, if selected, your story

could appear in

BRAKE & FRONT END.

Send digital pictures and your

contact information to:

[email protected].


v Industry Review

NUCAP Announces Industry-First 100Percent Brake Pad Performance GuaranteeNUCAP has announced its

industry-first 100 percent brakepad performance guarantee on allbrake pads manufactured withNUCAP’s NRS technology.

“Brake Pads produced usingNUCAP’s NRS technology pro-vide a mechanical bond that elim-inates any chance for edge lift,rust jacking or delamination,”said Jayson Keever, vice presi-dent of global marketing forNUCAP. “Our extensive researchindicates that edge lift is one ofthe main causes of brake pad fail-ure. Our NRS technology wasdesigned to eliminate this, andwe feel so strongly about the ben-efits of NRS that we’re backingall pads that include it, regardlessof the manufacturer.”

Starting May 1, 2013, NUCAP

will launch its guarantee on allbrands of brake pads using itsNRS Retention System. For brakepads experiencing delaminationduring their useful life, NUCAPwill reimburse customers a flat$250 toward the cost of thosebrake pads and labor. “Brakepads featuring NRS are safer,experience less noise and lastlonger, and with our 100 percentguarantee, there’s never been abetter time to switch to pads withNRS,” said Keever. “We’re cer-tain that less delamination willresult in more profitable installersand happier vehicle owners.”

Learn more about the NUCAP100 percent brake pad perform-ance guarantee atwww.nucap.com/guarantee.

Tenneco’s Monroe Ride & Drive Program Expands Locations,Adds Industry Training Events in 2013Tenneco announced plans to attract nearly 10,000

attendees to its 45-stop calendar for 2013. Tenneco

also has plans to take the Monroe Ride & Drive

seminar to several key industry training schools,

including VISION Hi-Tech Training Expo in Kansas

City, MO, which took place in March.

Now in its 12th year, the Monroe Ride & Drive

program was designed to help technicians identify

the characteristics and differences of worn versus

properly functioning ride control components and

to recognize the impact these components have on

overall vehicle safety.

“We’re proud to continue to offer such a critical

educational initiative to the aftermarket,” said Chuck

Osgood, manager of training and sales operations,

North American aftermarket, Tenneco. “It’s such a

small investment of time compared to the remarkable

value you’ll bring back to your customers.”

The 2013 Monroe Ride & Drive program also fea-

tures enhanced curriculum, including key new ride

control trends, exclusive training in innovative

undercar technologies and the hands-on ride and

drive training experience. This premier driving

experience gives service technicians an opportunity

to compare the steering, stopping and stability

characteristics of vehicles with worn OE ride control

components and new Monroe ride control

replacement components.

To find out when the Monroe Ride & Drive pro-

gram will visit your region, visit the “Events” page on

www.monroe.com to see the most current schedule,

and to register to participate in an upcoming event.

Mighty AutoParts Celebrates50 Years OfAutomotiveIndustry Success

Mighty Auto Parts, a WallStreet Journal “Top 25” fran-chisor and automotive aftermar-ket parts distributor headquar-tered in Norcross, Ga., is cele-brating 50 successful years in theautomotive industry. The pri-vately held company has beensupplying original equipment(OE) manufacturer-quality parts,along with training, technology,systems and sales support sincefounder Dallas “Dick” Wallacebegan direct-selling parts in1963, using his VW as a mobileoffice.

Continues on page 16

v Industry Review

16 May 2013 | BrakeandFrontEnd.com Go to www.bfeRAPIDRESPONSE.com �Reader Service: Go to www.bfeRAPIDRESPONSE.com

Today, the company helps more than 12,000 auto repair profes-sionals, including new and used car dealers, independent repairshops, tire centers and national quick-service chains, profitablymanage and grow an exceedingly complex business, where bothtechnical and operational skills must constantly evolve.

In addition to a wide range of OE underhood and undercarreplacement parts, Mighty provides technical training and systemssupport to help auto service businesses excel in every area of fixedoperations. Mighty and its 114 locally owned franchisees provideinventory management based on local vehicles-in-operation dataand trends, not national averages, along with customized market-ing programs that help create customer satisfaction and retention.

“We started with the simple idea of personalized, direct partsdistribution to our nation’s auto service providers 50 years ago,and that philosophy of putting people first hasn’t changed,” saidKen Voelker, president and CEO of Mighty Auto Parts. “In fact,it’s our focus on the human factor that allows Mighty to consis-tently anticipate and meet the needs of our customers no matterhow rapidly our industry changes.”

Raybestos TrainingModule ExpandsTechs’ ProfessionalSkills

Technicians can further enhancetheir installation and service skillswith e-learning training modules fromRaybestos chassis parts — a memberof the Affinia family of brands. Thetraining module is available atwww.RaybestosChassis.com and canbe studied free of charge.

The Raybestos Advanced CertifiedEducation (ACE) program increaseseducational opportunities for techni-cians and service writers who sellRaybestos chassis product. The e-train-

Continued from page 14

Industry Review

� Go to www.bfeRAPIDRESPONSE.com BrakeandFrontEnd.com 17


ing module offered by Affinia Tech Training pres-ents the ideal customer service engagement whenassessing chassis repairs and addressing customerconcerns.

The e-training modules offer technicians thesetime-saving and money-saving benefits:

• Identify and resolve undercar problems more effectively;

• Make it easier to present and sell appropriate parts and service;

• Learn key advantages of Professional Grade products;

• Reduce comebacks for work that doesn’t meet customer expectations; and

• Increase loyalty with existing customers and grow business with new customers.

For more information, visitwww.RaybestosChassis.com or

call 800-323-3022.

Standard Motor ProductsNamed Federated OutstandingVendor Of The Year

For the second consecutive year, the Federated Auto

Parts membership has selected Standard Motor Products

(SMP) as its Outstanding Vendor of the Year.

“When we tallied up the votes for the Outstanding

Vendor of the Year, it was nearly a photo finish between

many competent suppliers, but one stood out as the over-

all winner, Standard Motor Products,” said Bo Fisher,

Continues on page 18

Industry Review

Go to www.bfeRAPIDRESPONSE.com

chairman of Federated Auto Parts. “SMP earned our top honor again this year

because of their commitment to excellence in areas such as education, plus

their creativity in new products and market segments. We congratulate SMP

and thank them for their dedication to the success of our membership.” Fisher

presented Federated’s most prestigious vendor award to Standard Motor

Products during the group’s national meeting and annual awards dinner held

April 25 in Orlando, Fla. Accepting the award on behalf of SMP were Bill

Collins, Robert Frick, Matt Guden, Bob Kimbro, Alex Simmons and Ken

Wendling.

In addition to the Outstanding Vendor of the Year award, Federated pre-

sented its Outstanding Supplier Support Awards to its supplier partners that

excelled in five key categories:

Education and Training Vendor of the Year – DensoElectronic Cataloging Vendor of the Year – DormanMarketing Vendor of the Year – Federal-MogulOrder Fill Vendor of the Year – East PennSales Representation Vendor of the Year – Gates “Each year, Federated members choose the supplier partners that stand out

in areas important to the overall success of Federated. It takes teamwork to be

successful and we thank these deserving MVP suppliers for their outstanding

performance for the Federated team,” said Federated CEO Rusty Bishop.

Continued from page 17

Continuing its tradition of assist-ing members in boosting profitswith promotions, sweepstakes andincentive trips, Automotive PartsAssociates (APA) recently treated sixenthusiastic race fans to the excite-ment of Kansas Speedway in once-in-a-lifetime fashion. Mike and LisaWilson from Campbell’s Auto Service in Riverview, New Brunswick,Canada; Steve and Denise Doney from Hometown Tire in Williston,VT; and Larry and Larry Schultz from Larry’s Service Center in Linden,WI, were the lucky six people who came to Kansas City on an all-expenses paid trip.

Beyond meeting NASCAR drivers, getting autographs and photos,and hanging out in the garages and even the pits, the winners watchedtwo races with mostly cooperative weather. This Speedway Weekend isan annual promotion for Automotive Parts Associates, but this is thefirst year it’s been held in conjunction with the April race.

The promotion ran from January through March of this year andProfessionals’ Choice Warehouse Distributors gave every customerwho purchased a product from one of the sponsoring manufacturers anentry form for a chance to win.

The sponsors were: Airtex Fuel, ASC Industries, Bosch, Denso,Dorman, Federal-Mogul, FRAM, Gates, KYB, MAS, NGK and SKF.

For more information, visit www.professionalschoice.com.

Automotive Parts Associates TreatsRace Fans To Kansas Speedway Weekend


Even with the best infor-mation available to theprofessional tech, there

are times when some things justdon’t add up or are omitted inthe description of how a certainsystem works.

Dealing with unforeseenproblems ends up in a never-ending stumbling block of falseleads, misguided diagnostics,or, for the lack of better term, atypical “snafu.” There are a lotof situations when the techjust has to trust his ownjudgment and go with whatseems right, rather thanwhat all the information issuggesting. Call it a gutinstinct, dumb luck ormaybe a professional guess,but that may be all youhave to go on.

Case in point, a bodyshop sent over a pickuptruck with the “CheckGauges” light stuck on.The gauges checked fine,there were no servicecodes, and no apparentreason why this warninglight should be stuck on.They all matched their actualreadings — from the segmenttests on the individual gauges,to the values from each of thegauges. Plus, the gas gaugewas spot on, and nothingregarding the water temp,charging system, etc. looked

out of place.I called the body shop and

asked them what they repairedand what components theychanged. As it turns out, theproblem was the result of arather light hit on the driver’s-side front fender area. Therewas no frame damage and nomajor components werereplaced.

Withmy initial

tests completed,everyone was leaning

toward a problem with thedash cluster itself, but I wasn’tconvinced. Since it was an insurance job, the pressurefrom the body shop and theinsurance company to find theanswer was by just replacing

the cluster, than it was to chal-lenge the results.

For me, it comes down totest, retest and test again. I justcouldn’t bring myself to replac-ing the cluster just yet. I wantedsome definitive proof beforegoing through all the hassle ofreprogramming, and setting themileage and security system. Ifthe gauges tested good, howcan I justify calling them bad?

The more I conducted vari-ous tests, the more confused I

got. I poured over thedescription of how the

“check gauges” functioned.I was hoping to find some

clue that might tell mewhat I was missing.Nothing stood out —absolutely nothing.

I needed to takethat leap of faith

that I was rightand it wasn’t thecluster. It was abig gamble, I’ll

have to admit. I stuck with theidea that the tests were accu-rate and the problem had to bearound the damaged area.There again, not knowing whatI was looking for put me in theposition that it was all “blindfaith” that my test results wereright, that I was right and therewas something else wrong.

Then, after removing theinner fender, I found a two-wire

By Scott “Gonzo” Weaver [email protected]’s Tool Box

Taking a Leap of FaithWhen Relying on Your Knowledge and Expertise is the Best Diagnostic Plan

connector dangling all by itself.As I moved the wire through thespace, using the wire length togive me some idea as to where itmight go, it ended up at the bot-tom of the battery tray. It’s thebattery temperature sensor con-nector. I’ve run across these beingdisconnected on older modelsbefore, and it’s always associatedwith a code, but not this time.

After plugging it in, the“check gauges” warning wentout. Just to verify the wholething, I unplugged the sensorand tried it again, and, sureenough, the “check gauges”warning light stayed off.

I still think it’s pretty odd thatin all of the operating descrip-tions, there was never any men-tion of the battery temperaturesensor as part of the “checkgauges” warning system. It’s notthe first time I’ve run into some-thing that didn’t make sense orthat wasn’t explained in a waywhere I could understand theengineering behind it. You’d liketo think that every possible sce-nario has been checked and dou-ble-checked by the engineers, or

at least they’d mention some-thing about it like: “Oh, by theway, we tied the battery tempsensor to the ‘check gauges’warning light, and thought youmight like to know. And, don’tworry, the gauges are fine.”

It seems that with all the sophistication we’ve added tothese modern cars, there are stillsome things that haven’t beenfully explored regarding the pos-sibilities that could arise. These“leaps of faith” in today’s mar-ketplace don’t leave any roomfor exploratory surgery to isolatethese problems, and unless youknew about these quirky prob-lems beforehand, your diagnostictime could get lengthy.

I can’t say every answer is ina scanner or manual. Techshave always had to find solu-tions to a lot of problems thatwere not even thought to beproblems when these systemswere created, especially when acertain circuit or communica-tion line gets crossed up andthrows a monkey-wrench intoyour diagnostic plan. �


Gonzo’s Tool Box

Alignment Spec

Normal driving usuallywon’t knock thewheels out of align-

ment or damage the suspen-sion. However, normal drivingalso involves encounters withthe unexpected, which oftenincludes potholes, curbs, rail-road crossings (which are fa-mous for being rough),parking lot speed bumps andother things that jar and stressthe suspension. For this reason,periodic alignment checks area good way to ensure properwheel alignment and to detectdamaged, worn or bent partsthat might need attention.

Take a bent steering arm, forexample. A bent arm willchange toe alignment. Toe mis-alignment can scrub the rubberoff a set of tires as fast as anylead-footed teenager with anattitude. Only 1/8 inch of toemisalignment produces scrubequivalent to dragging the tiresideways 28 feet for every milethat’s traveled! So if you see afeathered wear pattern on thetires or what looks like camberwear on the inside or outsideshoulders of both front tires(radials primarily), toe is prob-ably out of alignment.Shoulder wear on both outsideedges can be caused by toe-inwhile shoulder wear on bothinside edges can result fromtoe-out.Measuring the distance

between each control arm andwheel is another way to find a

bent steering arm. Both dis-tances should be the same onboth sides of the vehicle. If onearm is closer or further fromthe wheel than the other, it willnot allow equal toe changes onboth sides when the wheels aresteered.Pulling down the suspension

and checking for uneven toechanges side-to-side is yetanother “trick” that can beused to find this kind of “hid-den” damage. If a steering armis bent, one side will show agreater toe change than theother.If you find evidence of a bent

arm (unequal toe-out changeor a difference in the distancefrom the steering arm to thewheel side-to-side), it may notbe obvious which arm is theone that is bent. Obviously,there is a difference, but whicharm is the one that is bent?You may have to comparesteering arm to wheel meas-

urements on another vehicle ofthe same year, make andmodel to determine which armis bent.

CAMBER CLUESCamber can affect directional

stability. A vehicle will leadtowards the side with the mostcamber. So always comparecamber readings on both sides.More than half a degree differ-ence can cause a steering pull.

If camber is off on one sideonly, a close encounter with apothole or curb may have benta spindle, control arm or strut.A shift in the position of a struttower can cause the samething. A shift in the position ofa crossmember, on the otherhand, will usually change cam-ber on both sides.

One way to identify hiddendamage that may be affectingcamber is to do a“jounce/rebound cambercheck.” Raise the suspension


Sponsored by:

Bent Arms and Struts

Damage in a knuckle may result in a distorted bearing bore.

four inches and read camber onboth sides. Then compress thesuspension four inches and readthe camber angles for both wheelsagain.

Different camber readings side-to-side with a jounce/reboundcamber check usually indicates abent strut that needs to bereplaced or straightened. If thereadings are the same, a check ofthe “steering axis inclination”(SAI) angle side-to-side shouldalso be made.

SAI, THE DIAGNOSTICANGLE

You can zero in on the hiddendamage (a bent or mislocatedstrut, bent control arm and/orbent spindle) by comparing theSAI angle, camber reading and“included angle” (the anglebetween camber and SAI). Here’s another way to check for

strut problems. Loosen the twocamber adjustment cam bolts onthe strut (if provided), push thesteering knuckles in as far asthey’ll go towards negative cam-ber and measure the distancebetween the strut and brake rotoron both sides. Then compare read-ings. If both distances are thesame, you can rule out misalign-ment at the bottom end of thestrut or a bent spindle. If they’re

different, one of the struts is bent.Bending a strut to “realign” the

front end is no answer becauseyou shouldn’t fix one problem bycreating another. Bending a strutmay bring camber back into range— assuming the wheel isn’t offmore than one and a half degrees(which is the maximum limit forbending any strut). But bending aperfectly good strut to compen-sate for misalignment elsewhere isgoing to create unequal camberchanges side-to-side duringjounce and rebound which maycreate a bump steer condition.There is also a risk of weakeningthe strut, which may lead to strutfailure later.To check for a bent strut shaft,

loosen the large shaft nut at thetop of each strut and rotate theshaft 360 degrees while keepingan eye on the camber reading. Ifthe shaft is bent, the top of thewheel will wobble in and out,and the camber reading willchange as the shaft turns. Nochange in the camber readingmeans there’s nothing wrongwith the strut. A strut with abent shaft must be replaced.There’s no way to safely straight-en this kind of damage becauseattempting to bend a hardenedshaft will likely crack it. �


Alignment Spec

Even with the toe adjusted and the steering wheel straight, a bentsteering arm can cause the SIA to be out of specification. The samealso applies to bent strut rods and camber.

ABS Function

There was a time whenadvancements in braketechnology were entirely

hardware based. The changefrom drum brakes to discbrakes, the introduction ofsemi-metallic and ceramicbrake pads, and the addition ofpower brakes as standardequipment were all changesthat were all achieved by re-designed and improved brakesystem components. Today,electronics is driving most ofthe advancements in brakingtechnology.It started with anti-lock

brakes (ABS). When ABSbecame part of the brake sys-tem, the ability to control indi-vidual brake circuits electroni-cally opened up a whole new

world of possibilities. Onewas to get rid of the mechani-cal brake proportioning valveso the rear brakes could han-dle a greater percentage of thebraking load to reduce stop-ping distances. ElectronicBrake Distribution is nowcommon on many vehicles.Traction control and stability

control came next. With thehelp of the ABS pump andhigh pressure accumulator,traction control can apply thebrakes as needed to prevent orcontrol wheel spin. On someapplications, it functions like alimited slip differential toimprove traction on slipperysurfaces. Stability controlemploys individual wheelbraking to counter oversteer

and understeer. This improveshandling stability and reducesthe risk of rollovers in SUVsand other vehicles.

BRAKE PRE-CHARGINGAs braking technologyevolved, the next step was tomake the brake system smarter.On some vehicles, the brakescan now anticipate stops evenbefore the driver can react. Bymonitoring throttle positionand vehicle speed, softwarechanges allow the brake systemto pre-charge the brakes theinstant the driver's foot lets upon the accelerator pedal. Lightpressure is applied to thebrakes in anticipation that thebrakes will soon be applied.

According to research per-


By Larry CarleyHOW SOFTWARE IS

formed by Audi, priming thebrakes reduces the time it takes toapply the brakes by 100 to 200 mil-liseconds. At 80 mph, this canreduce the overall stopping dis-tance by 23 feet or about one carlength — which may be enough toavoid or mitigate a collision.

"Brake Assist" is a variation of thisapproach that senses when the driv-er is braking hard as opposed tobraking normally. By monitoring therate at which the brake pedal isbeing depressed, the system canincrease the amount of brake force tohelp the vehicle stop more quickly.Additional inputs from the ABSwheel speed sensors, vehicle speedsensor, yaw and acceleration sensorsand accelerator pedal may also beused to determine if the vehicle isbraking normally or if the driver isslamming on the brakes.

One caution you have to keep in mind when work-ing on vehicles that have some type of brake pre-charging system is that the brakes have to be dis-abled before you begin any work onthem. If the vehicles does not have amanual deactivation switch, thismay require using a factoryscan tool or aftermarket bi-directional scan tool to accessthe vehicle's brake controller soit can be turned off. Anotheroption would be tolocate the brakecontroller fuse andremove it.On applications where

the ABS pump and high pres-sure accumulator are used forpower-assisted braking, the high pressureaccumulator should be completely dischargedbefore you open any hydraulic lines. Pumping thebrake pedal 30 to 40 times with the ignition keyOFF can do this.

One some Mercedes applications, things get a bittricky. To deactivate the brake system, remove thekeyless entry fob from the vehicle, then lock thedoors. Move the key out of range from the vehicleso the system cannot be accidentally activated.After 30 seconds, the Sensotronic braking systemshould time out and go into sleep mode. Do notunlock the vehicle while any brake work is beingperformed and do not touch the brake pedal. Oncethe work has been completed, the system needs tobe reactivated using a multi-step procedure thatinvolves cycling the ignition on and off once, thenquickly cycling the steering wheel side to side. Thiswill wake up the system and cause it to pre-chargethe brakes.

REDUCING BRAKE FADEOn some vehicles, the brake controller monitor

brakes use when the ABS, traction control or stabilitycontrol systems are intervening. The controller keepstrack of vehicle speed and to what extent the brakesare being used so the brakes don't get too hot. If thecontroller estimates the brakes are overheating

(which occurs around 900 degrees F.), it may tem-porarily discontinue ABS, traction control and/or

stability control to give the brakes achance to cool down.

A similar approach is used byBMW with their "Brake Fade

Compensation" system. In2006, BMW made softwarechanges to its ABS systems

on its 3-series modelsthat allows the brake

controller to compensatefor brake fade under harduse by increasing theamount of power-assistprovided by the ABS

pump. The software algo-rithm can estimate fairly

accurately the temperature ofthe brake pads without using an

actual brake pad temperature sensorto predict how much the brakes are starting to fade.As the calculated pad temperature goes up, the sys-

ABS Function

BrakeandFrontEnd.com 29

CHANGING BRAKING

ABS Function


tem applies more power assistto compensate for any loss offriction. This provides a moreconsistent pedal feel withoutdecreasing braking effectivenessor increasing stopping distances.

On most vehicles, the driverhas to press harder and harderon the brake pedal when thebrakes are getting really hot tomaintain the same braking effec-tiveness. On some cars andSUVs, the brakes start to faderather quickly when they aresubjected to repeated hard brak-ing. But it does provide a feed-back signal to the driver to backoff a bit so the brakes can cool. Ifthe driver fails to realize what ishappening, and continues toride the brakes, the brakes mayget so hot that they fail com-pletely — and that's somethingnobody wants!Because brake fade compensa-

tion is programmed for the hotfriction characteristics of theoriginal equipment brake pads,it should be obvious that any

replacement brake

pads for these vehicles shouldhave friction characteristics thatclosely match the original pads.If somebody installs pads thatvary too much from the originalpads, the amount of brake fadecompensation applied may notmatch the fade characteristics ofthe new pads, resulting in toomuch compensation or notenough. This is something thatboth friction suppliers and tech-nicians will have to keep inmind as these more sophisticat-ed braking systems come intogreater use.

HILL HOLDINGSoftware tweaks to the brake

controller can also provide a"Hill Holding" feature on somevehicles. Monitoring the move-ment of the wheels via thewheel speed sensors and theposition of the gear shift leverand clutch pedal position allowsthe brake controller to detectany rolling forwards or back-wards when the vehicle stopson an incline. The systemapplies the brakes to prevent

the vehicle from rollingwhile it is

ABS Functionstopped, then releases the brakeswhen the clutch starts to engage.This makes it easier for driverswho are not very adept at drivinga stick shift to stop on hilly ter-rain.On some SUVs, such as Jeeps,

software changes allow the brakesand stability control system toprovide a "Hill Descent" feature.This allows the driver to concen-trate on steering and take his footcompletely off the brake pedalwhen descending a steep offroadtrail. The hill descent system mon-itors the rate of decent and usesindividual wheel braking to keepthe vehicle straight as it descendsthe hill at a safe pace.

ADAPTIVE BRAKINGSoftware has also allowed the

brakes to be integrated with

"Adaptive Cruise Control" sys-tems that allow a vehicle tomaintain a consistent followingdistance as the pace of trafficchanges. Most use radar to meas-ure the distance to the vehicle infront, but some use optical sys-tems. When the lead vehicleslows, the adaptive cruise controlsystem automatically appliesgradual braking to maintain asafe following distance. If thevehicle ahead suddenly brakes,some systems will give a hardpulse to the brake to alert thedriver while others will take overand apply the brakes if the driverfails to react in time.

AUTOMATIC BRAKINGBy adding hardware that can see

the road ahead (radar or opticalcameras, or both), automatic brak-

ing has even become a reality onsome high-end luxury vehicles.Volvo, Mercedes and others nowoffer some type of automatic brak-ing system that will apply thebrakes if the driver fails to react.

These systems detect cars andother objects ahead of the vehiclewith their radar or optical sys-tems. The relative rate of closure isconstantly being calculated todetermine if the driver needs to bewarned. If the driver fails to slowdown or brake, a warning lightmay flash or a chime sound. If thedriver still fails to react, the auto-matic braking system takes overand either begins to slow downthe vehicle (collision mitigationbraking) or bring it to a completestop. Some of these systems onlyslow the vehicle above a certainspeed while others may apply fullbraking as needed. It's essentialthat the drivers of these vehiclesfully understand how their auto-matic braking system works, whatit will do and won't do, and whenit will and won't intervene. OnVolvo's XC60 City Safe system, forexample, full automatic braking isonly used at low speeds and doesnot intervene at speeds above 18mph. Volvo says up to 75% of allaccidents occur at speeds of lessthan 30 km/h. So an automaticbraking system that can preventor lessen the severity of accidentswithin this speed range has thepotential of significantly reducinginsurance claims and repair costs.

Some SUVs are also combiningautomatic braking with objectdetection when backing up.Visibility behind many SUVs isvery limited from the driver's seat,so automatic braking kicks in ifthe ultrasonic backup sensorsdetect anything behind the vehiclewhile it is backing up. �


Tool Cool By Andrew Markel, Editor

Caliper ClampingForce GaugesI

n most cases, the clampingforce gauges are installed inplace of the inner brake

pad. Once in place, the caliperpistons are pumped out to takeup the gap and then clampingpressure is measured.

This is not a direct measureof the pressure in the brakesystem. It is the amount offorce being generated by thecaliper pistons. If you had thecaliper piston’s diameter, youcould use the result of this testto calculate the pressure in thebrake system. The clamping force of each

caliper should be roughlyequal. There is not much inthe way of guidelines to sayhow much side-to-side differ-ence is acceptable, so you haveto use common sense. Again,theoretically, the clamping

force should be equal, butreal-world results will notalways show this. A rule of thumb I follow is

unless the side-to-side differ-ence can be associated with asymptom, such as prematurepad wear or brake pull, don’tworry about it.These tools will directly help

identify sticking caliper pis-tons and indirectly help iden-tify hydraulic restrictions.

ABS APPLICATIONSA clamping force gauge can

also be used to diagnosis ABSand Electronic BrakeDistribution (EBD) HCU prob-lems. One of the most com-mon failures for HCUs can bedump/isolation valves thatare stuck open. This problemcan be the most elusive todiagnose. Solenoid valves canremain open due to contami-nated brake fluid, rust andsediment. Also, copper fromthe brazing materials in thehard lines is attracted to thevalves and seats of the sole-noids.

Symptoms can range fromthe rear pads wearing outearly to pulling conditiongoing away only when theABS is activated.

Use the clamping force gaugein the bay to measure differ-ences side-to-side and front-to-back. �


Control Arm By Andrew Markel

Ball Joints, Tie Rods andControl Arms Wear Out?

The ball and socket joint has beenaround on animals and humans formillennia. This simple design has

been used on vehicles since the turn of thecentury because it works. But, just like ourhip joints, ball and socket joints, like balljoints, tie rods and sway bar links, wearout.

If you went to the doctor and in theexamination he pulled out a pry bar anda large set of pliers, you might get a lit-tle scared and fear that his diagnosismight be more damaging than the actualproblem. The same is true for ball jointsand tie rods. Any OEM- or suspensionmanufacturer-recommended procedurefor inspecting a ball-type joint rarelyinvolves a pry bar and almost neverinvolves a set of pliers. Just like a doctor,you must use your hands and eyes.

BALL JOINTSUnlike a rubber bushing, a spherical

ball joint is designed to pivot throughmultiple planes. Of course, because theball joint constantly pivots at differentangles, it tends to wear more rapidlythan do bushings.Ball joints can be broken down into the

load-bearing and non-load (follower) bear-ing categories. A load-bearing ball joint isdesigned to support the weight of the vehi-cle while providing a hinge point for thesteering system. Most load-bearing balljoints are designed to cancel the effects ofnormal wear by centering themselves intheir own sockets.Non-load-bearing ball joints or follower

style, on the other hand, are designed to


Why do Automotive

Control Arm

maintain precise dimensionaltolerances in a steering or sus-pension system. Wear in a non-load-bearing ball joint willcause a noticeable change in thecamber, caster or toe angle of afront suspension. Consequently,non-load-bearing joints are pre-loaded in order to compensatefor wear. Unloaded control armball joints, for example, shouldbe tested for preload when thesuspension system is disassembled.

A ball joint is made up of ahousing, ball stud, bearings,end cover and Belleville washeror spring. A Belleville washer isa conical-shaped springdesigned to be loaded in theaxial direction. The joint isattached to a control arm bypressing the joint into the armor riveting the joint to the arm.If the joint is pressed into thearm, it will require a specialtool to remove the old joint andinstall the new one. Failedpressed joints can be difficult toremove because of corrosionbetween the control arm andjoint. This is especially true

where a steel ball jointhousing is pressedinto an aluminumcontrol arm. When thejoint is riveted to thecontrol arm, the rivetsare drilled out or cutwith a air chisel. Thenew joint is replacedusing bolts and lock-ing nuts.

Tie rod end balljoints, on the otherhand, are more toler-ant of wear. Providingan assistant is availableto turn the steering

wheel of the vehicle in a parkedposition, the “dry-park” testingmethod will indicate excessivewear in most tie rod ends.

Inner tie rod ends found onsteering racks should be testedfor excess wear by listening fora knocking or clicking noise asthe steering is turned. Whateverthe method used, rememberthat small amounts of wear ineach tie rod end can add up to amajor variation in toe angle.Technicians often have a prob-

lem locating valid specificationsfor ball joint testing. In manycases, a vehicle manufactur-er’s warranty tolerancesare simply too liberalfor real-world align-ment situations. Inother cases, a manufac-turer simply leaves theissue to the technician’sindividual judgment.This allows for the real-world effects that cumulativebushing and ball joint wear willhave on the steering and sus-pension system as a whole.If you use a pry bar and brute

strength, your inspection could

be influenced by the bushings inthe control arms. If you use aset of “water pump pliers” tocompress a tie rod, it will giveyou a false reading almost everytime and is not a measure ofwear for some types of tie rods;even some new tie rods willcompress.

It may look dramatic to thecustomer, but it could get youin a load of trouble. Many dis-reputable shops have used thistechnique to increase sales andmany repair shop regulatorsdisapprove of this method. Fordand other OEMs recommendtechnicians use their hands topull and push on tie rods to feelfor play.


Control Arm

BALL JOINT INSPECTIONSome ball joints that have a

grease fitting use the fitting as awear indicator. If a grease gunwill not couple to the fitting, thejoint needs to be replaced. Asthe joint wears, the Bellevillewasher or spring maintains the

tension on the bearings to main-tain zero axial endplay as thecontrol arms move. Lateral wearcauses the ball stud to moveinside the bearing. It can affectcamber and tire wear. TheBelleville washer or spring willnot compensate for lateral wear.

INSPECTIONLoaded Joint: To check a

loaded ball joint, place a jack orjack stand under the lower con-trol arm to support the weightof the vehicle. Attach a dialindicator to the lower controlarm and locate the dial in a ver-tical position to measure axialrunout at the steering knuckle.In the case of an all-wheel-drivefront ride strut or independentRWD, it may be necessary tomount the dial at the CV joint.Moving the steering knucklecan check lateral runout.

For a SLA suspension that hasthe coil spring over the top arm,the upper joint is loaded. Tocheck the joint, the upper con-trol arm is supported to unloadthe joint. If the ball joint has abuilt-in wear indicator, jointplay should be checked whilethe vehicle is on its wheels.

Follower Joint: To check a fol-lower-type joint, the Bellevillewasher or spring is loaded orcompressed to check for axialend play. For a strut-type sus-pension, place a jack standunder the cradle to allow thestrut to fully extend. Attach thedial indicator clamp to thelower control arm and locatethe dial in a vertical position tomeasure axial runout at thesteering knuckle. Place a jackunder the ball joint and load thejoint by raising the jack. Turn


Control Armthe steering wheel and observe the ball joint tocheck lateral runout.For a SLA suspension, the upper control arm

can be blocked and the joint can be compressed.Attach a dial indicator to the steering knuckleand place in a vertical or parallel position tomeasure axial runout at the lower control arm.Moving the steering knuckle can check lateralrunout.

There are specifications for alignment, rideheight and ball joint end play. The overall condi-tion of the chassis is important to the safety andperformance of the vehicle. In the area of safety,it is a good practice to cover your assets. Try toconvince the owner of the vehicle that it is impor-tant to correct all of the conditions that couldcause the vehicle not to perform safely. If this isnot possible, make sure that all conditions notrepaired that affect safety are made a part of therepair order and a disclaimer is attached.

TIE ROD INSPECTION BY THE NUMBER1. Check the outer tie rod ends by grasping BY

HAND and push up and down. DO NOT USE APRY BAR. Check the inner tie rod ends, pushingthem front to rear. If any free play is observed ina joint, it is worn and should be replaced. Keepreading for additional Ford and Lincoln tie rodinspection tips.2. While vehicle is on the ground or on a drive-

on hoist, have an assistant rotate the steeringwheel rapidly back and forth from 10 o’clock to10 o’clock while observing the inner and outer tierods. If the outer tie rod ends have any verticalmovement or the inner tie rod ends have any hor-izontal movement, the tie rod end with theobserved movement should be replaced.3. Raise the vehicle and remove the front

wheels. The wheels will need to be turned to theright in order to inspect the passenger-side innertie rod end and to the left to inspect the driver’s-side inner tie rod end. Inspect all four seals fortears, perforations and wear. If there is any indi-cation of wear or perforations on the seal, that tierod end should be replaced.4. Stud Corrosion: Using a putty knife or other

hard, flat, dull object, lift the bottom of the sealup, exposing the stud. If any water escapes fromthe seal in the form of bubbles or in a liquid form,that tie rod end should be replaced. Closelyexamine the stud for signs of corrosion, especiallyaround the knuckle. A rag might be needed toclean off any grease on the stud that impairs agood visual inspection. If there is any sign of cor-rosion, that tie rod end should be replaced.

If you find play at the inner tie rod, confirm thatit’s the joint, and not the rack bushings, that areworn. If the rack boot allows it, squeeze the boot tofeel that the joint is the problem and the rack isn’tloose and moving in the housing. This will also giveyou an indication if the rack boot needs to bereplaced. It’s always a good practice to replace theboot, but you may find it’s easier to obtain a tie rodend rather than a direct-fit boot. Some of the uni-versals fit well, but if you have to order the tie rodend, add the boot kit to the order.

With outer joints, it’s a good practice to makenote of the length of the rod before the end isremoved to get the toe in the ballpark onreassembly; many techs simply count the turnswhen the rod is removed, but a measurementfrom the center of the joint to a known point is agood back up. Either way, be sure the toe is with-in specs before the car is returned. �


Brake Job By James A. Blair, Contributing Writer

THE PROBLEMBy now, the majority of tech-

nicians know that brake rotorthickness variation is the con-dition that generates yourtypical brake pulsation con-cerns. Hopefully, they alsounderstand that “lateralrunout” of the rotor is theunderlying culprit. There aremany great articles written onthe topic of lateral runout andmethods of preventing andeliminating it, including, butby no means limited to, clean-ing the rotor mounting sur-faces, properly torqueing thewheel assembly, and use ofan on-the-car brake lathe. Inthis article however, I wouldlike to examine two atypicalcauses of thickness variationthat can have a “problemvehicle” back at your shopagain and again if notaddressed. (A problem vehi-cle will typically be back inabout 3000 miles or so!)First of all, even if lateral

runout were corrected toabsolute zero, it’s only tempo-rary! As a matter of fact, evenafter refinishing the rotor withan on-the-car brake lathe, youwill probably have somerunout right after re-installingthe wheel! Unless of course,you torque ALL the lug-nutsto specification by turningthem equally and at exactly atthe same time like the factoryinstalls them!

The one cause that is not typ-ically addressed, in no smallpart due to lack of a method,is the brake caliper not releas-ing the pads sufficiently,which can really only becaused by two things:

• The caliper slide mecha-nism binding causing the out-side pad to not properlyrelease; and

• The piston sticking in itsbore causing both pads to notproperly release.

Sure, we all clean and lubethe caliper slidemechanism(s), right? But whatif for example, a caliper bolthas been cross-threaded orbent causing the bolt to becrooked? Or, on a slidingcaliper, the knuckle is bent sothat the caliper does not slidefreely enough? How do wecheck that?

CHECKING THE SLIDEMECHANISMThe easiest and most effec-

tive way to check this is tofirst clean and service the slidemechanism, then with pistonfully retracted and padsremoved, bolt the caliper backon. (And, yes, torque thebolts!) Then manually slidethe caliper back and forththrough its full range of travelwhile keeping it parallel withthe rotor. It should slidesmoothly and freely from oneend to the other.

CHECKING THECALIPER PISTON

Now, before the piston stick-ing issue can be addressed, weneed to make sure we under-stand the mechanism thatcauses the piston to retract inthe first place.

The caliper piston seal is of a“square cut” design. Note thaton the earliest disc brake sys-tems the seal resided in asquare groove and the pistondid not retract at all. Newercars, however, have one


A DIFFERENT “ANGLE”ON BRAKE PULSATION

Brake Job


minor, but very important modification; the out-side edge of the groove (the edge of the groovenearest the inner brake pad) is cut at a slight angle(the angle varies between 15 and 30 deg. depend-ing on manufacturer design). (Fig 1) This angleallows the seal to flex slightly on brake apply (Fig.

1) Then when the brake is released the seal thenreturns to its normal shape pulling the piston backto its original position. (Fig 2) (It’s important tonote that if the pads have worn enough, the sealwill actually make contact with the angled edgeand stop. The piston will then continue to move,slipping on the seal allowing the piston to adjustfor wear.)

NOW THE QUESTION BECOMES, HOWDO WE VERIFY THAT:1. The piston is not sticking in its bore.2. The piston is retracting the desired amount.For example, we could check for piston sticking

by using a spring gauge to measure the forcerequired to push the piston back in. Question is,how much force should it take? There is no servicespecification published that I’m aware of. But I’llget back to this in a minute.

Measuring the retraction is actually fairly easyusing the following procedure.

CAUTION: Leave the other caliper(s) installed orplace a suitable piston stop in it to prevent the pis-ton being pumped out of the caliper!

With pads removed, brake hose still connectedand piston fully retracted:1. Mount a dial indicator to the caliper housing

and load it 0.020” or so (Fig 3).2. Have a helper push the brake pedal down

SLOWLY until the indicator moves 0.020 or sothen hold it until the reading on the dial indicatorstabilizes. (Fig 4)

3. Zero the indicator. (Fig 5)4. Release the brake pedal.5. Now read the relative movement indicated.

(Fig 6)How much did piston retract? It better be at least

0.002” MORE than the manufacturer published lat-eral runout specification! The 0.002” is based onpersonal observation after measuring many vehi-cles, so your mileage may vary. But you got theidea. So, if the piston retracts 0.006”, your spec is

Figure 3: Mount the dial indicator

Figure 4: Load the dial indicator by depressingthe brake pedal.

Figure 5: Zero the dial indicator.

Brake Job

probably going to be 0.004” giv-ing you 0.002” clearance whenthe brake is released.

And, this checks the piston forsticking at the same time as itcan’t retract properly if it is stick-ing in its bore. Piston retractioncan also be measured at variousintervals throughout the pistonstravel. (I have seen several ofthem stick in only one area.) Thisworks on multiple pistoncalipers as well due to the factthat it is NOT the hydraulic sys-tem, but the piston SEAL that isdoing the retracting. So as longas you can depress the brakepedal and get the piston to movethe 0.020” or so you need, ifworking properly it should stillretract regardless of the action ofthe other pistons. So you mayhave to block the other piston(s)to get the piston you’re checkingto move but it still works.Although it really doesn’t take

much time once you get thehang of it, I do not check this onevery disc brake job that comesthrough the door. I’ve found it

invaluable however for problemvehicles or those with highmileage and/or calipers tooexpensive to replace simply on ahunch.

JAMES A. BLAIR

• ASE Master Certified• ASE L1 Certified• ASE P2 Certified• ASE Master Engine Machinist

Certified

From technician, service and partsmanagement, contract trainer, tech-nical representative to shopowner/operator, Blair has workednearly every facet of the automotiveservice industry since those part-time jobs at service stations duringhigh-school. Blair has been a fulltime automotive instructor since2000. In August 2012, he acceptedthe lead instructor position at NewRiver Community and TechnicalCollege in Ghent, WV, and wastasked with developing both a newautomotive and diesel program. �


Figure 6: Take the reading. (Note that the dial moves back-wards in this application.)

TPMS By Andrew Markel, Editor

Since TPMS became standard equipment

in 2008, many sensors are starting to

show their age. While some of these

sensors may have a lot of battery life

left, the sensors stems are starting to

fall victim to corrosion. Here are five

tips that can help you avoid snapping

stems and have the shop eat a sensor.

1. REPLACE VALVE CAPSIf someone put a chrome or steel valve cap onto an

aluminum stem, there will be galvanic action causingthe cap to seize to the stem. The appropriate valvecaps are plastic or aluminum or a valve caps thathave a nickel coating on the outside to prevent them

from seizing. Many manufacturers are findingthat their cars in the salt belt states that

have the correct aluminum valve capsare still experiencing corrosion and capsare sticking to the stems. Some manu-facturers are recommending that youchange all the valve stem caps to plastic

caps. Depending on where you live, thismay be a good proactive course of action.

2. ADVISING A CUSTOMER ABOUTSTUCK VALVE CORES

A valve core stuck in the stem can be a productivitykiller and potential problem for your shop and cus-tomer. The core can become stuck due to corrosionor crossed threads. You have three options and alloptions involve telling the customer before possiblysnapping off the stem. The first option is to leave italone and tell the customer about the condition. Thiscan prevent getting a car stuck in the bay or the cus-



Sensor Corrosion5 Tips to Help Avoid a Snapped Stem

TPMStomer stuck in your waiting room. The secondoption is to exceed torque limit when trying toremove the valve core. It could come loose or itcould snap the stem. Make sure to sell the customera sensor before attempting this. The third option is todrill out the old stem, tap the opening and install aspecialty replacement stem. All three methodsinvolve telling the customer ahead of time beforeattempting to remove the valve core. It is not yourfault if a stem breaks due to corrosion.

3. ASK IF PREVIOUS TPMS WORK HASBEEN PERFORMED

If a customer brings a car in with a TPMS light on,ask them if there has been any previous work per-formed on the vehicle and if any sensors have beenreplaced. Hopefully, your shop replaced the sensor,but if another shop did the work, you need to checkthe sensors before you give the customer an accurateestimate. If one or more sensors do not look like theothers, you could be stuck in a diagnostic conun-drum. Some aftermarket sensors need to be pro-grammed by proprietary methods to clone the OEsensor. This can be a problem if your shop does nothave the tool.

4. NO MORE DISH SOAP AND WATERWater and dish soap have always been the tire tech-

nician’s best friend. But, to the TPMS sensor, it canbe it’s worst enemy. Water inside the rim and tirecan cause corrosion. Also, dry air and humid airhave different properties. It will cause the TPMSlight to come on sooner as the tire cools or heats up.Use only mounting paste. The price of a small bucketof paste is less than the cost of a comeback.

5. ALWAYS INSTALL A NEW NUTThe best way to prevent corrosion is to replace thekit every time the sensor is removed or disturbed.The typical kit includes a nut, valve core, grommetsand valve cap. Each component has a specific func-tion and lifespan that is not only determined by time,but what happens when – and after – it is installed.This goes for sensors that are six months old or sixyears old. TPMS fastener nuts are designed inanodized aluminum to eliminate the contact of twodissimilar metals that would create galvanic corro-sion and material deterioration. The nut has a bond-ed lubricant to help provide the proper torquerequired for seating a new grommet. If a nut isreused, the anodized surface may be scratched awayand corrosion could occur between the sensor, wheeland the stem. �


If your shop is not in California, the replace-ment of the catalytic converter is simple andtypically there is only one replacement option.

Most shops understand that they must replace theconverter and that using a test pipe or bypassingthe converter is bad for business and against theEPA regulations and could result in big fines.

Converters must be certified and be labeledwith the correct codes that are stamped intothe shell. You can not just install a converterthat matches the size and shape. Certified con-verters may have more precious metals andcatalyst biscuits. Another problem is within the calibration of

the ECM of the vehicle. California emissions-certified vehicles may have more sensitive oxy-gen sensor calibrations. If a non-certified con-verter is used, the efficiency codes may goaway at first. But, they could return after thecatalyst becomes loaded with contaminates. This year, things are getting complicated. It is

starting in New York and will probably impactthe other 48 states. The issue is vehicles that weremanufactured for the California market findtheir way to other states. New York is the firststate to mandate that a vehicle with Californiaemissions and converters must always bereplaced with a CARB-certified converter, even ifit is never going back to California. There have been long standing policy debates

in Maine, Washington State and other states onemissions testing and standards. But so manyof these proposals are stuck in limbo as the fine

points and funding for these initiatives are dis-cussed and lobbied for on both sides.

As a shop, you are charged under the EPAClean Air Act to keep vehicles running withinthe emissions parameters they were initiallysold with. It is a broad interpretation, but it isthe safest for shops to follow. Additionly, alsobe aware of local emission requirements thatcan change not only from state to state, butcounty to county.

Converter


CATALYTICCONVERTERReplacementis Changing

READING THE LABELS Every vehicle sold since the

1970s has a label under the hoodon the hood underside, struttower, radiator support, fanshroud or firewall indicating theemissions calibration. California Emissions Certified

models have California, CARB orARB on the label. This informa-tion is vital when looking upparts in the application catalog,to ensure proper fit and also innavigating state-mandated after-market replacement converterregulations. In New York, starting June 1st

2013, replacement converters forCalifornia emissions-certifiedvehicles licensed in the state ofNew York must be CARB-com-pliant. This includes 1993, 1994or 1996 models. It is still legal touse EPA-compliant converters inthese two circumstances:

1.) Vehicle model year 1995, orvehicle models older than 1993;and

2.) Federal / EPA OnlyEmissions Certified vehicles,regardless of model year.

NOTE: CARB does not certifyany aftermarket converter for any

vehicle less than six years old.

READING CATALYTICCONVERTER LABELINGAftermarket replacement cat-

alytic converters are labeled withimportant information necessaryto ensure that installations com-ply with California law. Newaftermarket converters producedand sold before January 1, 2009are labeled according to U.S.EPA requirements. A code in thefollowing format will bestamped or affixed to the shell ofthe converter:T/CA/MC XXXX YYYYT: Either “N” (for new after-

market converters), or “U” (forcertified used converters). ARBstaff has found that this charac-ter is sometimes omitted on newaftermarket converters.CA: Indicates that the convert-

er has been ARB approved. MC: A two character code for

the converter manufacturer. XXXX: The converter’s part or


Converter

Converter


series number. The number may be longer than 4digits. YYYY: The date of manufacture. The first two dig-

its indicate the month, and the last two the year.The manufacturer code and part number informa-

tion can be used with the manufacturers’ catalog toverify that the converter is approved for installationin California on a particular vehiclemodel. Converters currently Californiacertified for use on OBD II vehicles alsohave “OBD II” (or “OBD2”) stamped oraffixed to the shell of the converter. Belowis a list of valid manufacturer codes forCalifornia.

MANUFACTURER CODESAD: Advanced Car Specialties Ltd

(RiteCat). AE: The Automotive Edge (Hermoff) AT: AirTek, Inc. (Catco) BN: Brown Recycling &

Manufacturing, Inc. BO: Bosal Mexico SA

DECV CA: approved for

CaliforniaCE: Car Sound Exhaust

System, Inc. (Magnaflow)

CT: Valina, Inc. (CarTex) CV: Cateran Pty Ltd.EM: Eastern Manufacturing, Inc.EQ: Equipo Industrial Automotriz S.A. de C.V.ES: ESW America, Inc.ET: Emico Technologies, Inc. LP: LaPointe Exhaust System Equipment

MC: MillerCatalyzer CorpMM: Maremont N: new aftermarket

converterPA: Perfection Auto

Prod. Corp PP: Products For Power

TA: WalkerManufacturing/Tenneco

TD: TRI-D Industries Inc.TP: Tested Products (DEC)

An example of what the labeling lookslike is provided on page 54. For this example, thelabel indicates:

•“N” - this was produced as a new aftermarketconverter

•“CA” - approved for use in California •“TA” - produced by Tenneco, but marketed

under the Walker brand name. •The series number is 200300 •“09 05” - It was manufactured in September 2005 •“OBD II” - It is approved for use on specific

OBD II applications. The label for convertersapproved for use in California after January 1, 2009are slightly different: D-XXX-XX YYYYYY ZZZZ. D-XXX-XX: This is the ARB approval number for

the converter (known as the “EO number”). EveryEO number will begin with “D”. The first three X’sare a 3 digit number corresponding to the manufac-turer. The last two digits are the specific approvalnumber for the manufacturer. The EO number can beused to obtain information about the approval statusof the converter on ARB’s website in the same man-ner that other aftermarket add-on and performanceparts can be looked up. The website address ishttp://www.arb.ca.gov/msprog/aftermkt/devices/amquery.php.YYYYYY: The part number for the converter

(assigned by the manufacturer).ZZZZ: The date of manufacture. The first two dig-

its indicate the month, and the last two the year. �

Wheel Bearings By Gene Markel

Wheel Bearings &Wheel Speed Sensors

If you are replacing awheel bearing on a late-model vehicle, you will be

dealing with a wheel speedsensor. In the past decade,wheel speed sensors havebeen moving from differen-tials, axles and knuckles to in-side or on the wheel bearingor hub unit. At this location,the sensors are more accurateand often more protectedfrom the elements.

The average wheel bearingjob may require a scan tool,scope or meter to verify theoperation of the sensor. Mostvehicles in use today use twotypes of wheel speed sensors— variable reluctance (pas-sive) and magnetoresistive(active).

VARIABLE RELUCTANCE(PASSIVE)

The variable-reluctancemagnetic sensor has a per-manent magnet pickup coreand coil surrounding themagnet. These are typicallyfound on pre-2003 vehicles.The sensor is mounted at aspecific gap from a notch-and-tooth reluctor ring.These sensors are less accu-rate and might read 3-5 mphon a scan tool when the vehi-cle is sitting still. The rotation of the reluctor



ring increases and decreases the magnetic fieldbetween the notch and the tooth to generate avoltage in the coil. As the gap between the notch and the ring

changes with the rotation of the reluctor, the sen-sor generates an analog sine wave voltage signal.The voltage signal will increase in amplitudewith an increase with the speed of the reluctorring. The change in amplitude can affect theswitching toggle to the computer where a crackedreluctor ring may produce an extra switching tog-gle. The variable-reluctance sensor is a two-wiresensor in a hub unit between the bearing races.

MAGNETORESISTIVE (ACTIVE)A Magnetoresistive sensor has a sensing element

that contains an output module mounted on asubstrate and magnetic material. These magneticrings are often located on the seal of the bearing.The magnetoresistive sensor’s main advantage isthe ability to sense direction and operate with awide air gap. The sensor is more stable in high

vibration conditions and operates more efficientlythan the reluctance sensor.

The sensor can detect the direction of rotation ofthe reluctor ring and zero speed. The sensor’scompact size allows it to be incorporated into ahub bearing utilizing a alternating magnetic polereluctor ring that is built into the rubber seal. Amagnetoresistive sensor can be a two- or three-wire sensor. The three-wire sensor has a power,ground and signal connector pin.

The two-wire sensor has a power and signal con-nector pin. The ground is a part of the mountingfor the sensor. The Philips magnetoresistive wheelspeed sensor power input can range from 12 to 5volts from the ABS controller.

The sensor produces a square wave signal with ahigh signal of 1.93 volts, and a low signal of 0.64volts. The high signal must cross 1.29 volts and thelow signal must cross 0.97 volts to low. The mainadvantage is that the amplitude of the signal doesnot change.

Wheel Bearings

Wheel Bearings


DIAGNOSTICPROCEDURES

The diagnosis of a trouble codeor problem condition requires aninvestment in information andtools. The information and scantool are expensive and are a

good reason to charge for diag-nostics. Diagnosing a DTC orfailure condition should start byconducting a Technical ServiceBulletins (TSB) search from yourinformation data base. The con-dition may already exist and

there is a known fix that can savetime and money.

SCAN TOOL RETRIEVALOF DIAGNOSTIC TROUBLECODES AND DATA

The scan tool is the most effi-cient tool for diagnosing ABSsensor problems. If you are serv-icing three and four year oldvehicles, your shop cannot func-tion well without it. A DigitalVolt Meter (DVM) and oscillo-scope are used to verify a DTC orproblem. An oscilloscope is theultimate DVM. It measures volt-age and time and many scantools have a built-in scope. Youcan survive without a scope, butyou have to have a good DVMthat can measure frequency.Frequency can provide informa-tion that a signal is present.

OSCILLOSCOPEThe use of an oscilloscope can

be a time consuming process thatrequires a certain amount ofinformation to accurately displaya wheel speed sensor wave pat-tern. The following contains informa-

tion for setting up an oscillo-scope. The average automotivetire ranges from 24 to 28 inchesin diameter. At one revolutionper second, the vehicle would betraveling at a speed of four tofive miles per hour.

The frequency of the sensorwould give you an estimate ofthe number of teeth on the reluc-tor. This information will helpyou set the time base for yourscope. The time base is set toallow all of the signals per revo-lution to appear on the display. Ifa wheel rotates at one revolutionper second, the sensor and tone


Wheel Bearings


ring produces a 32-Hertz (Hz) frequency signal, thetime base is calculated by dividing the frequencyby 1.

This would be 0.03125 second, or 30 millisecond(mS) rounded down to the nearest mS. Set the timebase for 30 to 40 mS. The amplitude of the signalfor a inductive sensor will change as the speed ofthe reluctor increases. This will also affect the oscil-loscope display. A low amplitude signal can indicate an air gap or

high resistance connector condition. If the oscillo-scope you are using has a feature that will allowyou to capture a series of frames, it will allow youexamine the trace of one revolution of the reluctor.A cracked, damaged or missing reluctor can pro-duce a signal that may not be processed by theBCM. The square wave signal does not need to beprocessed by the BCM; it is a direct input. TroubleCodes C1141 thru C1144 can be caused by a miss-ing tooth and can be verified with a scope. The aftermarket technician has to be more profi-

cient in diagnosing system failures. He or she hasto be familiar with more than one manufacturer

and be able to understand their methods of diagno-sis verses the dealership technician who deals withone manufacturer. The scan tool and service infor-mation are the primary tools, but a thoroughknowledge of fundamental mechanical and elec-tronic component operation is also an importanttool in finding the right fix the first time. �

32 Teeth

MISSING

DAMAGEDCrackedNORMAL

CRACKED

DAMAGED

MISSING

OSCILLOSCOPE PATTERNS

RELUCTANCE

DIGITAL

1.13V

0.64V0.97V

1.29V1.93V

TIMERELUCTANCE DIGITAL

Electrical DrawBy Scott “Gonzo” Weaver, Contributing Writer

Hunting With A Voltmeter

In the past, I’ve always hunteddown parasitic draws with mymultimeter set on the amperage

scale in series with the batterycable, along with jumper leads toopen and close the connection, so Icould watch for the amperage drop.I also needed to know what a safelevel was in order to see the actualdraw (or lack of). Some techs use adead-man switch attached to thebattery post instead of jumperwires. For me, it’s whatever I havehandy at the time, and time ismoney so the quicker I can get tothe source of the problem, the bet-ter that is for my bottom line.

Sometimes, these draw tests cantake hours to complete, dependingon what module you’re looking atand the length of time it takes topower down (Sleep Mode). I find itnot only awkward, but a little con-fusing, to have all of these deviceson an adjacent worktable or balanc-ing precariously on the edge of thefender.

One thing you need to know toproperly perform the draw test isthe correct values for each system’sparasitic draw. I find it a lot easierto watch the meter values droppingoff to their sleep mode when I havea pretty good idea as to which mod-ule it is. But this requires me tostand over the meter and be readyto pull fuses (if needed) at amoment’s notice, all of which istime consuming, involves lots of

64 May 2013 | BrakeandFrontEnd.com Go to www.bfeRAPIDRESPONSE.com �

PARASITIC DRAW

Electrical Draw

� Go to www.bfeRAPIDRESPONSE.com BrakeandFrontEnd.com 65

connections that have to be working correctly, aswell as a lot of patience on my part. With too manyvariables, something can, and usually does, gowrong. When it does, I think there has to be a betterway. I really would like to have a way to at least isolate

the offending circuit quickly, efficiently and accurate-ly without all these hassles. How about a way I cansee the draw without disconnecting anything? Nopulling fuses, no need for a dead-man switch and noneed for that temperamental amp meter hook-up,which we all (me included) forget to switch backwhen we check voltage thenext time we need themeter. Well, there is…

Before parasitic draw test-ing, it was the tried-and-true old test light methodbetween the battery postand cable. While it wasn’tprecise as far as voltage oramperage, it was accurateenough and it got the jobdone. If the test light waseven partially lit up, therewas a draw. I never worriedabout the actual amount; it wasn’t as important asthe “where is it.” So, how about a way to locate thesedraws in a late-model car and not worry so muchabout the exact values; just find the problem andleave all that technical mumbo-jumbo aside. There isa way, and all it takes is your voltmeter.

Start with a good multimeter (DVOM) with an mVscale (millivolts) and a couple of good test leads withsharp, pointed ends. Put the meter on the millivoltscale and your test leads on the two test points onthe back of the suspected fuse, and then measure thevoltage. Yes, put the negative lead from your meteron one of the fuse test terminals and the positive leadon the other. (On some fuses, these little test spots ontop of the fuses are quite small, so this is where thesharpened points of the test leads will help out.) A good practice session for this method is to try this

on a car that is working. Find the dome light fuseand watch the meter. If there is no current flowacross the fuse, the meter will read a flat zero. Ifthere is a current flow in the fuse, you will measure asteady voltage drop of some sort from the time thedoor is opened to the time the dome light finally

goes off. It doesn’t matter what the voltage is, justthat it is there.

The reason this works is that all circuits have someresistance in them. This resistance to current flowcauses a minute change in the voltage readings fromthe source to the load itself. Current flow also createsheat, heat increases resistance and current flowthrough this resistance is seen on your meter as avoltage drop. Any voltage measured across the fusethen indicates some current flow.

If you get a small, fluctuating voltage, you’reprobably not on the fuse test points. This is where

those sharp testprobes really helpout again. Thereshould be either novoltage at all, orsome sustained volt-age level that will beconstant. Just likeany other testingmethod, practicemakes perfect, andtrying this out on acar with no prob-lems is a good way

to see how this whole thing works.Some mV meters are so sensitive that you may even

see a fluctuating voltage reading as you get close tothe fuse, or in the air around the circuit when it’s nothooked to anything. If so, try touching the two leadstogether before you hook it up. If all is well, themeter should read zero voltage at that point.

I prefer this method to the amp meter testingmethod. During the process, I’m not disconnectinganything, I’m still looking at a voltage drop (notamperage) and I’m less likely to screw up anotheramp fuse in my meter. I’ve even had success withthis by starting at the MAXI fuse, then following thewiring diagram to break it down even further until Ifound the source of the draw.

The only time I start pulling fuses is after I’ve got-ten the draw isolated to one section of the wiringdiagram or fuse box. I’m not concerned so muchwith accurate values or amperage loads, just wherethe draw is originating. The fact that I’m seeing volt-age on the meter in a circuit that shouldn’t have anycurrent movement is enough information for me tosuspect that this circuit is the culprit. �

Tech TipsThis month is sponsored by:


CORROSION ISSUES WITH FUEL FILLER NECKS Since the introduction of the

OBD II system, manufacturershave continued to improve onthe monitoring of evaporativeemissions, with the completeevaporative system being undera scrutinized surveillance.Codes like P0440 to P0456 areall related to the fuel vapor con-trol, including leaks.

Starting early this century,manufacturers have increasedthe development of fuel vaporretention, preventing thevapors from escaping into theatmosphere. This promptedmany changes in the design andlocation of certain componentssuch as charcoal canistersmounted near the fuel tank.

A fuel tank pressure sensor isused to monitor the pressuredecay in the system during thetesting and will turn on thecheck engine light if the pres-sure decay moves out of specifi-cation. Remember that theevaporative system test will notbe performed if the fuel level isbelow a 1/4, as it would causefor too much pressure buildupin the tank or simply wouldtake too much time to build anypressure. A helpful tool to identify leaks

is a smoke-generating machine.During the smoke machineprocess, loose or broken hosesare usually identified as themain cause of evaporative fail-ures. An additional componenthas started to surface and isbecoming the leading cause of

evaporative emissions leaks —the fuel filler neck.

Most fuel filler necks are madeof steel and are secured to thefuel tank via a rubber hose. Thefuel filler neck is usuallyenclosed in the rear fender well,where an accumulation of dirtand debris causes the filler neckto rust and leak. These modelsare hard to diagnose, as theinner fender protection must beremoved to get access. Othersare totally exposed behind thefender where plashing and roaddebris erosion removes paintand perforates the filler neck.

The filler cap, which besidesnot being properly secured afterrefueling, may cause multiplefailures of the system as well.The fuel filler cap may have adefective control valve and pre-vent pressure hold in the sys-tem. Second, the filler neck itselfmay have rust on the outerseam, which will prevent thecap from sealing properly to thefiller neck. On some models, thepart where the cap screws on ismade of plastic and can be dam-aged by the fueling nozzle wheninserted during refill, which willprevent proper sealing.

All of these situations willcause the check engine light toturn on. Make sure to imple-ment fuel filler neck inspectioninto your regular vehicle main-tenance or during fuel tankremoval to prevent comebacks.

Courtesy of Spectra Premium.


A Day in the Life of a Contaminated 02 SensorSince the oxygen sensor is in

the exhaust stream, it canbecome contaminated overtime. Much like a spark plug,the oxygen sensor can beexamined and “read” todetermine what the cause ofcontamination might be.

• Black sooty depositswould indicate an excessivelyrich fuel mixture condition or oilblow-by in an older engine.

• A common type of contamina-tion is due to coolant being burntin the combustion chamber likelydue to an engine gasket leak.

• Lead poisoning is no longercommon, due to the lack of leadedfuel, but the emulsifying of the“terne” plating inside a steel fueltank due to the excessive use offuel system cleaners or alcohol cancause this same condition.

Typical Switching OxygenSensor Diagnosis• Look at the sensor voltage

when the engine is cold and theignition is first switched on. Theheaters will cause the sensor toconduct current. Watch for thebias voltage to gradually lower asthe sensor heats.

• Watch for the sensor to comedown to less than 100 mV withinthree minutes of KOEO time.After three minutes, all sensorsshould have about the same volt-age with the KOEO. A failed orcontaminated sensor may beslow or may not get down to 100mV at all.

• If one of the sensor voltagesremains high, that sensor couldbe causing a no DTC driveability concern.

Oxygen SensorReplacement• The primary sensor is on the

manifold or the exhaust pipe; late-model vehicles also have sensorsfarther downstream. Becausemany late-model vehicles havemultiple oxygen sensors, be sureyou correctly identify the bad sen-sor so you do not mistakenlyreplace the wrong one.

Vehicle manufacturers identify“bank1” vs. “bank2” and“front/rear” vs. “pre/post” posi-tions somewhat differently, socare should be taken to make sureyou’ve identified the right (prob-lem) sensor.

• Unplug the wire connection,then spray penetrating lubricantonto the threaded connection.

• Use an appropriate oxygensensor removal tool.

• Most oxygen sensors come


Tech Tips 02 SENSOR

Tech Tips 02 SENSOR / PONTIAC GTO

Some 2004-2006 Pontiac GTO customers may com-ment on a knock noise from the front when driving atlow speeds over bumps or uneven road surfaces.

This condition may be caused by the lower coil of thespring touching on the side lip of the spring seat. Theillustration shows the rub mark on the spring coil.

The spring coils contacting the body sheet metalwithin the wheelhouse area may also cause this condi-tion. To make the appropriate repairs, follow theinspection and service guidelines below.

SERVICE PROCEDURESInspection1. Inspect the tightness of all front suspension fasten-

ers. If they are OK, proceed to Step 2.2. Inspect the body sheet metal around the inside of

the strut tower for signs of spring coil rubbing.3. Inspect the second lower coil on the inboard side

of the spring for signs of chipped or marked paint, asshown in the illustration.4. If marks are found as described in Steps 2 and 3,

proceed to Procedure A.

with a special electrically conductive anti-seize com-pound applied to the threads, so it’s merely a mat-ter of threading the new sensor into the void left bythe old one.• If the new sensor does not have anti-seize pre-

applied, be sure to apply some to the threads priorto installing the sensor. Do not put excessiveamounts of anti-seize onto the threads. Getting anti-seize compound on the sensing area will contami-nate it.• Always check the appropriate reference material

for the required torque specification. Once it’s snug,plug the connector into the vehicle’s factory wiringto finish the task.

• Using Mode $06 Test Data– Once an oxygen sensor repair is made, Mode $06

data can be useful to determine if the oxygen sensoris operating correctly and the repair was effective.

– Mode $06 is the actual system test data that OBDII looks at when it decides to set a pending or cur-rent fault code.

• The chart on page 64 is an example of the Mode$06 data that can be obtained with regard to theoxygen sensors.

Courtesy of Delphi Product and Service Solutions.

GTO Front End Noise

Tech TipsProcedure A1. Remove the spring from the

strut assembly and re-install itupside down (with the thin coilend resting on the spring seat).2. Carefully reinstall the upper

bearing (yellow plastic housing),ensuring that it is located correctlyin the upper spring seat.3. While the strut is removed

from the vehicle, cycle the controlarm up and down. If a noise isheard from the lower control armrod front insulator bushing, rein-stall the strut assembly to the vehi-cle and proceed to Procedure B. Ifno noise is heard, install new strut-to-steering knuckle attaching bolts(Pontiac P/N 11090821) and nuts(Pontiac P/N 92138205). Tightenthe nuts while applying pressureto the top of the brake rotor. Thiswill ensure that the camber adjust-ment bolt is against the strut tube,eliminating the need to perform afront end alignment.

Tightening Procedure

1. Tighten the nuts to 85 N.m (62lb ft).2. Tighten the nuts to 100 N.m

(74 lb ft). Tighten the nuts anadditional 90 degrees.

Procedure BNOTE: Only perform this proce-

dure if Step 3 from Procedure Aconfirms that it is necessary.1. Remove the front lower con-

trol arm rod nut (1) (Pontiac P/N11076363).

2. Install a new nut,but do not fully tighten.3. Bounce the front of

the vehicle up anddown several times tostabilize the suspen-sion.4. Tighten the lower

control arm rod nuts to148 N.m (109 lb ft). �

Courtesy of AllData


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Centric Parts announcedseveral upgrades to its BrakeShoe programs. The new C-Tek Brake Shoe (110-Series)program offers a competi-tively priced entry-level op-tion covering more than1,000 of the most popular applications. The CentricPremium Brake Shoe (111-Series) program now includes higher frictionformulas specifically engineered for parking brakes. Centric has alsotaken this opportunity to update its Heavy Duty Brake Shoe (112-Series)program with enhancements to both the formulations and coverage. Reader Service: Go to www.bfeRAPIDRESPONSE.com

2001-2004 Dodge/Chrysler vehi-cles that have been trudgingthrough the ice, snow and salt thiswinter are especially susceptibleto Electronic Automatic Transmis-sion Control (EATX) module prob-lems. This is evident through poorshift quality, hesitation, decreasedfuel mileage or even the vehicleswitching into Limp Mode. Until now, your only option for replacementEATX modules was the expensive O.E. dealer. CARDONE’s 11 exclusivepart numbers of A1 CARDONE Reman EATX Modules offer O.E. perform-ance without the high price and are instock, ready to ship. For additionalinformation, visit www.cardone.com.Reader Service: Go to www.bfeRAPIDRESPONSE.com

CRP Automotive, a leading source of OE-quality replacement partsfor Asian and European import vehicle applications, offers a widerange of Pentosin OE-quality transmission fluids to cover a wide rangeof European vehicles, including popular makes such as Audi, BMW,Jaguar, Land Rover, Porsche, Volkswagen and Volvo. The Pentosintransmission fluid line is formulated on a fully synthetic base oil tech-nology and incorporates special anti-wear chemistry and friction modi-fiers to deliver safe and stable friction performance in various types oftransmissions – manual, automatic, and double clutch. For more infor-mation, visit www.pentosin.netReader Service: Go to www.bfeRAPIDRESPONSE.com


Federal-Mogul has introduced re-placement front brake pads for the2013 Ford Fusion and rear pads for2013 Dodge Dart passenger cars.These Wagner ThermoQuiet Ceramic-NXT pads are among several new padsets now available for leading late-model foreign nameplate and domes-tic applications. Wagner ThermoQuiet CeramicNXT brake pads representthe next-generation of automotive ceramic friction technology, with propri-etary formulations and other features that help ensure quieter and moreconsistent braking performance. Reader Service: Go to www.bfeRAPIDRESPONSE.com

Dana Holding Corporation has expanded its Spicer ring and piniongear options for Dana 44TM (226 mm) and Dana 60TM (248mm) rearaxles to include additional ratios, while ensuring top-of-the-line partquality through the manufacturing processes. New ratios available forthe Dana 44 and 60 axles include 4.56, 4.88, and 5.13, adding to ex-isting ratios of the Dana 60 axle that range from 3.54 to 7.17 and theDana 44 axle that range from 3.07 to 5.13. Reader Service: Go to www.bfeRAPIDRESPONSE.com

Standard Motor Products, Inc.(SMP) has added seven newclone-able sensors to its growingTPMS sensor line. These newclone-able sensors match theoriginal for fit, form and function;and due to their advanced engi-neering, they can easily becloned with the existing sensorID, eliminating the need for a fac-tory relearn. These new Standardand Intermotor part numberscover an additional 11 million VIOfor Acura, Honda, Ford, Chevro-let, Cadillac, Ford truck and Toy-ota truck through the 2013 modelyear. Reader Service: Go towww.bfeRAPIDRESPONSE.com

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Until now, those needing to replace a worn out or clickinghigh speed CV Joint on thedriveshaft of a 2007-’13 JeepJK were required to purchasean expensive driveshaft assem-bly, as high speed driveshaftservice components aren’tavailable from the OEM. Rockford Driveline now offersa money-saving alternative with their 2007-’13 Jeep JK Wrangler High SpeedCV Joint. The Rockford Driveline High Speed CV Joint fits both front andrear driveshafts, and comes “fully loaded.” The joint assembly is produced tomeet the design requirements of the original equipment manufacturer andincludes Rockford’s super-strength housing with precision-engineered internalcomponents, as well as the new CV boot, end cap, grease, and hardwareneeded to do the job right. Reader Service: Go to www.bfeRAPIDRESPONSE.com

Product Showcase

Product ShowcaseWIX Filters has launched a new XP line of high premium oil filters engi-neered to withstand the toughest of driving conditions and scientifically de-signed to maximize the performance of synthetic motor oils. XP filters areideal for vehicles subject to: towing trailers, boats and heavy equipment;high idling conditions in stop-and-go city driving; harsh driving environments,such as dusty and muddy roads; and extremely high temperatures. Premiumoil filters such as XP provide severalbenefits, including: wire-backed, fully syn-thetic media to trap more dirt, dust and grime, and a greater resistance tohardening and cracking due to silicone anti-drain-back valve.Reader Service: Go to www.bfeRAPIDRESPONSE.com


Tracer Products has introduced its new TP-9775-0008 Hy-brid A/C Compressor Oil for use in all hybrid vehicles. ThisOEM-based ester lubricant provides excellent lubricity andcompressor protection, while its high dielectric propertieshelp reduce the risk of shock hazard to technicians. Pack-aged in a convenient 8 oz. (237 ml) easy-pour bottle, thisformula is ideal for technicians who prefer adding oil to acompressor prior to installation. For more informationabout the Tracerline TP-9775-0008 Hybrid A/C CompressorOil, call toll-free 1-800-641-1133 or visitwww.tracerline.com.Reader Service: Go to www.bfeRAPIDRESPONSE.com


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It’s Fast, Easy and Accurate!Get FREE PRODUCT AND SERVICE INFO from the companies featured in this issue of Brake and Front End.

Advertiser Page AAPEX 61

Advance Auto Parts Professional 22, 23

ADVICS 43

Akebono Corporation 21

APA Management Group 55

Apex Supply Chain 51

Auto Value/Bumper to Bumper Cover 4

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Bartec USA, LLC 48

BaseLine by Coats 13

BendPak Insert, 74

Bosch 35

Campbell Hausfeld 50

CARQUEST Auto Parts 5

Centric Parts 30, 31

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Jasper Engines & Transmissions 67

Mevotech 41

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Nissan Motor Corp. USA 33

Nucap Industries 12, 80, Cover 3, Outsert

O'Reilly Auto Parts 39

Packard Industries 40

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Volkswagen Parts & Accessories 17

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Brake Story

Every technician knows it’simpossible to estimate howlong a set of brake pads will

last. But, due to changing owner-ship cycles, your customers are de-veloping new expectations.

According to R.L. Polk, thetypical consumer held onto avehicle for 57 months in 2012.This is up from 38 months in2002. So, if a customer drives15,000 miles a year, the cus-tomer will accumulate 23,000more miles before they tradeit in. These extra miles couldmean an extra front brake job.These repair incidents createpoints of reference that form cer-tain customer expectations thatwere not there just a decade ago.

But, in some cases, reality maynot meet customer expectations.Why? Each time the brakes areserviced, the pads could be com-promised by the previous brakejobs that did not restore the brakesto like-new condition.

The brake hardware might nothave been replaced during thefirst brake job. Halfway throughthe customer-expected life of thepads, the abutment clips may havecorroded and lost their spring. Theguide pins could have been neg-lected on the next brake job. Now,

the pads wear really unevenly andthe customer will notice thatmileage between pad changes hassignificantly dropped. Performinga complete brake job will breakthe cycle.

A normal customer-expectedwear interval cannot be achievedif a low-quality brake pad set isused. One area that is consistentlycompromised is the quality of thebacking plate and how it r etainsthe friction material during the lifeof the brake job.

Keeping a friction materialattached to a piece of metal undermore than 1,400 psi and shearingforces is not something to take forgranted when selecting a replace-ment brake pad. If the attachmentmethod and implementation issubstandard, it can result in noiseand, eventually, failure of the padbefore it’s worn.This is called edge lift or delami-

nation. It’s caused by failure of the

attachment method and can behastened by corrosion. The firstsymptom of the failure is noise.The noise is a result of the separa-tion, causing irregularities in thebraking surface and the pad now

having completely differentNVH properties.

Some manufacturers areusing mechanical attachment methods thatcan prevent delamination ina brake pad. The technolo-gy allows brake pads to berun down to the last few

millimeters of friction material.The bond can be resistant to shearloads, corrosion and heat. Thismakes for a pad that can meet orexceed a customer’s expectations.In a recent survey of technicians

and shops conducted by Brake &

Front End magazine, noise wasthe primary reason why a cus-tomer brought their vehicle in tohave the brakes inspected. Theydid not bring it in for a low-pricedbrake job. Customers are con-cerned about safety, not a lowprice. They can see the value ingetting more miles out of a com-plete brake job, over a cheap brakejob that has them returning to yousooner than expected. �


How Long Should a Brake Job Last?The Pressure Is On With New Customer Expectations

By Andrew Markel, Editor, Brake & Front End MagazineBRAKE PAD DELAMINATION

Brake & Front End

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Transcript of Brake & Front End