June 2009 MasterTechnician by Automotive Data Media

June 2009 | MasterTechnician Online

Contents

Feature Stories 16 Turbochargers Pt2: The Rise of the Machines by Greg McConiga

Last time, we covered history, operating principles, and design fundamentals. Now, for failures, diagnostics, and replacement alternatives.

30 Trimming the ABS... of Mid-’90s Chrysler Minivans by Kerry Jonsson

They’re getting to the age where their ABSs are starting to fail, andthe problems could be anywhere. Here’s a diagnostic approach that will save time and keep costs down.

42 Make Before Break Measuring Parasitic Currents by Wade Nelson

The rule of thumb is, “Anything under 30mA is acceptable, anything over 50mA indicates an excessive draw.”

52 Are You Ready for the Hybrid Highway? Part 2 by Tom Nash

In this second of two parts, we’ll delve into the components, the technologies, how to service hybrids, and where to find training programs and resources.

Cover Story 62 What happened to the 42V System? by Tom Nash

The really big deal that never happened. What caused these proposed high voltage systems to fizzle out?

Contents

Feature Stories

76 Another Mystery Solved: Hocus Focus by John Anello

A shop called me in to investigate a 2002 Ford Focus with 2.0L that had poor power on a hard acceleration.

88 A/C Leak Sealer: A Controversial Last-Resort Fix by John Hess

Bone of contention: Will A/C sealant save the day or destroy Western Civilization?

100 You Can Repair Runflat Tires by Dave Russ

You don’t need that old black magic to fix runflat tires.

112 Another Mystery Solved: Wheel of Fortune by John Anello

The Auto Tech on Wheels tells us how he used high-tech means to justify trans removal to find the real cause of a no-start

122 GM “U” Body Automatic Level Control by Greg McConiga

Even though this system is typically trouble-free, it’s on so many vehicles you need to know about it

Departments 6 Closed Loop By Bob Freudenberger

Letters to the Editor

12 Editor’s Page: IMHO By Bob Freudenberger

Observation and Celebration 4

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(Editor’s Note: We could’ve filled up this new section with praise from readers on what a great job Master Technician is doing. Our mission, however, is to use all the space we can to give you info that will help you in your demanding profession. So, we’ll concentrate on useful comments and criticism.)

Go-no-go and low pedal Dear Mr. Freudenberger, I read your article on valve adjustments (Jan., ’07 MT), and you did a great job on covering a wide range of vehicles and problems. I am so glad there is a new magazine out there for the complex automotive world we work in.

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Please do not take this the wrong way, but I was surprised that you did not suggest the gono-go feeler gauge. I am sure you are aware that even the greenest of technicians can get the proper clearances with a go-no-go feeler gauge. If that technician is looking for a 0.010 in. clearance, all he/she needs to do is grab a 0.009/0.011 in. go-no-go feeler gauge and adjust to a perfect 0.010 because the 0.009 part of the feeler gauge will slide in between the components being adjusted, but the 0.011 feeler gauge cannot slide in if the adjustment is 0.010. As you also know, if you can slide a 0.010 feeler gauge between two items the clearance is greater than the feeler gauge. I also enjoyed your article on the low brake pedal problems. With the increased heat conditions and traffic conditions a brake system has to go through each day it is extremely important to completely inspect the brake system before doing a brake service, and flushing the fluid is an

excellent suggestion for all vehicles, especially the ones that have ABS/ traction control systems. Thank you for your articles because even someone like me who has been in the automotive field for over 45 years needs to update his knowledge and share with other technicians to bring respect back to this most important trade. As you know, if you take twenty mechanics they will all have a different feel or outlook on anything. I am not concerned with the experienced mechanic such as yourself. I am concerned about our industry helping the inexperienced, or the experienced mechanic who will not admit he does not know how to do the job right the first time. Any steps we can take as an industry to avoid mistakes is important to us all. Keep up the good work, my friend. Sincerely, Eugene Field

You are right -- I certainly should’ve mentioned go-no-go gauges. I believe I bought my first set maybe 35 years ago, and I know they can help anybody who hasn’t developed the “feel” for this kind of work. But I’ve been comfortable with my own skills in this regard for so many years that I simply never thought of it. Maybe I’ll dig around in one of my rollaways to see if I can find my old set, and start using it again. Just as you say, helping our comrades avoid mistakes helps our whole industry, and gives our profession a better reputation with society at large. We pledge to try as hard as we can to “keep up the good work.” It’s committed, responsible people like you who make the incredible effort involved worthwhile. By the way, I’d thought working as a line tech was about as difficult a job as there is, but trying to put out the best magazine is beyond anything I ever imagined. At least it doesn’t beat up my old hands so much. B.F.

June 2009 | MasterTechnician Online

C l o sed Loop

More Mode $06 Hey, when are you guys going to get off the pot and give us more? I want more. I want more of Mode $06 -- every person I talk to goes, “Huh, what are you talking about?” So please in your infinite wisdom tell me where I can find Mode $06 info on Japanese and German cars. Thank you. Eric Radloff Believe me, Eric, we tried to get something out of both M-B and BMW on Mode $06, but neither seems to think it has any value except in the engineering process. We have especially close relationships with those companies since we at CmA produce technical magazines for them. But our service training and other tech contacts haven’t been able to help us. We’ll keep after them. As far as Asian vehicles are concerned, we had a story on Toyota’s use of this mode assigned to the

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foremost expert we know of, but he was unable to do it because of a job change. We’re still investigating it on our own (Honda, too) and will try to produce an article for a future issue, but we can’t say when. Magazine publishing is just like any other business: You’ve got to have the right people available at the right time. B.F.

CVT Omissions Bob, A couple of comments, not meant to be negative. The magazine is excellent as usual, but the CVT article [in the January issue of MT] makes no mention at all of service intervals, special oils, or anything that an independent shop can do in the form of service. My neighbor is a Chrysler tech. He claims that a quick lube added one qt. of Dex3 to a CVT trans and it was toast in 50 miles. The warranty was void. The quick lube had to pay for a trans at Chrysler. I would have liked to have seen some information like that in the article, assuming it is true.

Keep up the great work. Phil Fournier Phil’s Auto Service Hemet, CA A serious omission, indeed, Phil, which just proves that we can’t think of everything. That’s why we’re encouraging all of our readers to make the effort to tell us when we’ve missed something. We want MT to be as interactive as possible. B.F.

H2O In re-reading your article on antifreezes, I found a great discrepancy about using tap water: not enough coverage about it. I have never seen a shop that would take the time or money to buy distilled water. That is to say that I have not seen all shops. Most shops do not take this time as they find that it is too cumbersome to do and takes up valuable space. And they believe that the customer will never figure it out.

I personally use unmixed and distilled water in my own vehicles as I have only older vehicles, the newest being a ’96, and have had to replace the radiators in all. I do trust premix. I am like all other mechanics, I HATE WORKING ON MY OWN DAILY DRIVER. It really needs to be explained to these shops why it is bad and how they can really gain customers if the proper mix is done. The other thing I would like to know is if there is a litmus test for antifreeze to check for clorinate/ flouride in the system. Anonymous

We heartily agree that the subject of the water that’s half of the coolant mix is important. We’re planning a feature on it in an upcoming issue. We try to have a dozen tech articles in each issue, many more than our competing magazines have. Still, it’s impossible to cover every possible topic in every issue.

June 2009 | MasterTechnician Online

C l o sed Loop While we don’t know of a particular litmus test for water, you can go to your local Home Depot or Lowe’s and get a kit for about 10 bucks that will allow you to test for hardness, chlorine, pH, alkalinity, iron, etc. B.F.

More on low brake pedal Hi Bob, First, I want to thank you for making Master Technician available. I own an independent repair shop and have signed up all four of my techs as I feel it is a valuable resource for them and want them to take advantage of it. I am going to institute a standard practice of having each of them responsible for talking about an article from MT each month at our shop meetings. Next, I wanted to add my twocents worth regarding the “Low Pedal Lament” article. It was very informative and should help many

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techs with this common problem. Another thing I commonly see that causes a low pedal feeling, but wasn’t mentioned, is brake pads sticking or seized in their mounting bracket. Subarus and Toyota trucks are the most common ones I see. On Toyota truck/SUV front calipers of the rigidly mounted/multi piston design, if the pads aren’t seized in their brackets, then one or more pistons are stuck, which are almost impossible to detect unless the caliper or pads are removed so piston movement can be evaluated. This is such a common problem that when I’m on a road test unrelated to the brakes, I can detect with a high degree of success when this condition is present. I’m not sure if it is more of a regional thing with the road salt used here in the northeast. Visually inspecting the pads, rotors, etc. all looks fine, but when braking the pedal travels much farther than normal. This is the result of the additional hydraulic pressure needed to move the pads enough to provide adequate braking. When

Christopher M. Ayers, Jr. President/Publisher

cayers@cmacomm.com

I drive one of these cars I see it more as diminished braking power, but the customer and techs often interpret it as just a low pedal issue. Nathan Walker Recertified ASE Master Technician & L1 Walker Automotive, Inc. Wilmot, NH Dear Nathan, Your interesting comments just go to prove what I’ve always said: This is a regional business. I don’t see the same things in Florida that you do in N.H., esp. where undercar corrosion is concerned. Your points are so well taken that, if you don’t mind, I’d like to run them in a new “Closed Loop” section we have planned. All we at Master Technician want to do is help our readers get cars fixed right the first time, and info like this can sure help. Thanks for taking the time to write. -B.F.

Bob Freudenberger Editor

bfreud@cmacomm.com John Anello • Steve Campbell Paul Cortes • Kerry Jonsson Phil Fournier • Chip Keen Greg McGoniga • Tony Molla Tom Nash • Henry Olsen Matt Ragsdale • Dave Russ Contributing Editors

bfreud@cmacomm.com Christopher Ayers III Art Director, Project Mgr.

ayersc3@cmacomm.com Joann Turner Circulation Manager

jturner@cmacomm.com Kyle Ayers Web Master

kayers@cmacomm.com

Editorial, Circulation, Advertising Sales and Business Office: Master Technician Magazine 598 Pine Point Drive / Akron, OH / 44333 P.330.666.9886 • F.330.666.8912 If you have a letter to the editor, a Tech Tip or story idea, click here: bfreud@cmacomm.com, or on this website at www.mastertechmag.com. Master Technician is published by CmA Communications, LLC. The publisher and editors of this magazine accept no responsibility for statements made herein by advertisers or for the opinions expressed by authors of bylined articles or contributed text. The online version of Master Technician magazine is free to qualified automotive repair shop owners, managers and technicians. All other content on www.mastertechmag.com is available on a subscription basis. Visit www.mastertechmag.com for subscription information.

E d i tor’s Page

IMHO (In My Humble Opinion)

by Bob Freudenberger

Payday Back when Master Technician was a print publication, a reader wrote us this message: In the March, ‘07 issue, Bob Freudenberger mentioned an upcoming article on tech salaries. I loved working on customers’ cars in auto repair shops, especially momand-pop shops [but] they don’t want to (or can’t afford to) pay a decent salary, or benefits for a family, or pension, or anything else. That is why I now work for the city transit division. I don’t like the work! But they supply all the other aforementioned perks. The only way to stay in the auto repair business is to own your own business. I am considering leaving the auto repair business altogether because the local union employer is hiring and willing to pay almost DOUBLE the average repair shop and supply all the

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perks on top of that. YES, I do miss the challenge and the feel of figuring out the tough ones and the appreciation of a loyal customer. But if you read between the lines even the shops you talk about in your articles don’t want to pay a GOOD wage. That’s why Ron Ananian doesn’t have “an extra highly-trained technician available to help around the shop” And a lot of you guys are working more than one job. Fixing cars is great, but living life comfortably is the main reason we all get out of bed in the morning. Bill Hannigan

While the situation has changed somewhat now with dealership closings putting many techs on the street, I think my response is still worthy of consideration, to wit:

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E d i tor’s Page It’s obviously time for me to bite the bullet and at least start a discussion on this difficult subject, which seems to be taboo among polite people in this business. Sometimes you’ve just got to look the truth in the eye no matter how awkward or uncomfortable it is. And the truth is this: Most technicians aren’t paid nearly enough considering how much they have to know, how hard they have to work, and their investment in tools, not to mention their value to society at large. Even though most of us love the challenge and the satisfaction of this profession, many, many are leaving every day for greener, easier pastures. One of my neighbors once said, “I think mechanics are some of the smartest people in the world.” I agree, but, as the old retort goes, “If you’re so smart, why ain’t you rich?” While some people are simply swept along into a career path by life circumstances, most of us do make choices along the way. I, for one, could’ve made a lot more money over the years if I’d switched to being an ad salesman or publisher instead of remaining an automotive writer/ editor/photographer and technician, but those pursuits aren’t where my 14 MasterTechnician Online | www.mastertechmag.com

meager talents, or my interests, lie. I wanted satisfaction from my work. I’m thinking it’s the same with many techs. You could be doing something else that pays better, but you’re in love with fixing cars. Face it. The last place I worked as a line tech was indeed a mom-and-pop, just as Mr. Hannigan mentioned, although very technically sophisticated and profitable. Four bays, four lifts, two full-time techs, plus the proprietor, who is a tech and a half with great marketing skills, and his wife, who took care of day-to-day business. Well, everybody liked that friendly, family atmosphere, and customers became friends and grateful patrons who brought us pies, coffee cakes, cigars, wine, etc. Since there was plenty of lucrative business, everybody was well paid, too. I’m excruciatingly well-aware that I was blessed, and that the money part isn’t always that good elsewhere. That shop is in a location that had been all farms and woods when I was young, but has become an upscale bedroom community -- we call it the “wealth belt.”

So, we could charge enough so that everybody made a good living. This shop owner is so good he’d do well anywhere, but there’s no doubt that this “boom town” environment fostered success. For example, I remember a day when a young customer brought in both his new Mercedes-Benz roadster and his wife’s Hummer for routine maintenance. That was maybe a hundred and fifty thousand dollars worth of vehicles that we were taking on, probably for life, from just one household. That’s certainly not the norm across the country. Bottom line: Independent shop owner are going to have to learn to charge enough to support the great talent that keeps their businesses alive. I’m sure I’m going to get a “shipload” of e-mail messages and letters about this column, and how I didn’t really get into the problem, or suggest much in the way of solutions. Fine. That’s just what I want. Let’s see if we can fire up this discussion out there in the real world and make a difference.

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by Greg McConiga

Last time, we covered history, operating principles, and design fundamentals. Now, for failures, diagnostics, and replacement alternatives.

16 MasterTechnician Online | www.mastertechmag.com

et’s start by putting detonation into perspective: It’s the biggest problem with the high cylinder pressures that turbocharging can produce. Charge air coolers, proper compression ratios, proper turbo sizing and waste gate settings, engine temperature and fuel control, timing rates, quality fuels and tight oil control all help stave off these explosions.

Sub or supersonic While we’re on the topic, detonation is NOT and never has been colliding flame fronts. Flame fronts do not make noise when they hit. You can collide flame fronts all day long and never enter detonation. Ford twin-plug 2.3 and Nissan Nap-Z engines intentionally created two flame fronts, as have innumerable aircraft, racing and specialty engines. Normal combustion proceeds at subsonic speeds and spreads by thermal conductivity. Detonation is supersonic and spreads by shock compression. Subsonic and supersonic: propagated by heat, propagated by shock; that’s the difference. Detonation occurs

when the cylinder pressure and temperature cause the last bit of unburned fuel in the cylinder – called “end gases” – to spontaneously explode in uncontrolled combustion. Normally, a flame front rolls or proceeds through the air-fuel mixture in a few thousandths of a second – depending on air-fuel ratio and cylinder design it varies between .001 and .004 seconds – but the explosion of detonation occurs so quickly it’s measured in microseconds – literally thousands of times faster than a normal combustion process. Detonation exists in three phases: Inaudible (can’t even hear it over normal engine sounds), audible (the BBs or marbles-in-a-can sound we’re all familiar with), and hard detonation, which sounds like a really bad rod knock or someone with a big ball-peen under the hood. Trust me, you’ll know it if you hear it, and you won’t hear it long before you end up walking! In over thirty years I’ve only seen it a couple of times in a street vehicle, and in both cases it was too late. Depending on severity, detonation unseats rings, anneals parts, turns valves inside-out, sets

June 2009 | MasterTechnician Online

Tu r bochargers Part 2 up violent ringing vibrations in the assembly, breaks rings, cracks heads and blocks, destroys head gaskets, fractures piston tops and pounds the tar out of the reciprocating assembly. Diagnosing detonation is easy -the damage is so pervasive it’s like diagnosing a tornado. On a teardown, the piston top will be clean and appear almost sandblasted. The land above the upper ring may be beaten down and the top ring pinched. In a lot of cases, the piston will be burned down the side or have a hole burned through the dome. The upper half of the rod bearings and the lower half of the mains will show signs of fretting or damage. Piston pins may be stuck or sticky, rods twisted or cracked and crankshafts fractured. On spark plugs, you’ll see clean, almost sandblasted appearing porcelain and under magnification you’ll see tiny blue-black balls of molten aluminum stuck to the insulator. In loud highperformance engines, you’ll feel it before you hear it, and if it’s hard detonation you can’t lift fast enough to keep from tearing something up. For causes, think lean (less evaporative cooling during the gas exchange cycle), insufficient octane

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(the numerical measure of a fuel’s ability to withstand detonation), secondary ignition sources and overadvanced timing (lights the mixture early, and pressure builds while the piston is still trying to rise in the bore), too much compression or boost (or any other cause of high cylinder pressures), cam timing and profiles (early or late intake closing affects cylinder pressure) and overheating, either generally or locally (heat is pressure in a closed system.)

Brave new world Growing population aside, there are a lot of things looming on the horizon. Like all old technologies that grew into

If you spin it too fast, it comes apart! Now you know what a burst wheel failure looks like.

Tu r bochargers Part 2 modern applications, turbocharging is evolving. The improved efficiencies of variable nozzle turbines, wastegate elimination and ball bearing center housing rotating assemblies are just the start. Compressor and turbine wheel shapes are evolving, housing designs with multiple flow paths are on the market, and lighter titanium wheels and machined-from-solid parts are just entering the world of automotive turbocharging (you’ll recognize the titanium compressors – they will have cast iron compressor housings instead of alloy to meet burst wheel containment requirements -think a scattershield for 20 times the rpm of an engine).

Even wheel-to-shaft attachment methods are changing. The oldest design bore is smooth, with no threads in the wheel, retained on the shaft by a nut. The treaded bore is just that; the wheel bore is threaded and screws right onto the shaft. The latest wheels are boreless; they are bored and threaded part way through the wheel to eliminate the stress risers that emanate from a through-bored wheel face, which is a good thing at 100,000 RPM. Expect to see even more advances in gas and air flow control, and more improved oil control, better cooling, and reduced turbo lag.

Diagnosis and repeat failure prevention

New compressor and turbine wheels are not through-bored. On this “boreless” wheel, a partial bore-through is threaded, and the wheel threads directly onto the shaft. 20 MasterTechnician Online | www.mastertechmag.com

Given good fuel control and normal exhaust temperatures, clean, properly maintained and undiluted engine oil, watercooled center housings, properly maintained air filtration and just a few precautions on the part of the owner, a turbocharger will last the

life of the car. If these conditions aren’t met, there will be a failure, and if there is a failure there is very often little left to rebuild, especially in the event of foreign object damage (FOD), or lack of lubrication, the two most common turbo disasters. This is one reason that more and more rebuilding is moving to the manufacturers. Shafts, housings, wheels and bearings are often completely destroyed, making field rebuilding financially impractical.

Before grabbing a fistful of tools and tearing something apart, stop, look and listen. Most people know what a turbo-equipped vehicle sounds like. There’s that characteristic turbo sound, sort of a low pitched whistle that rises in pitch with engine speed. Take the time to road test the vehicle and see if you’re hearing and feeling what you should be hearing and feeling. You might just uncover an exhaust or intake system leak by listening, or you might hear something whirring or screeching that ought to be silent. Plus, if you know what it did before you’ll know that you fixed it when you do your final quality control road test. Oil-related failures are usually due to some manufacturer’s incredibly long recommended oil drain interval (What the hell are they thinking? Let’s see… $30 oil change , or $2,000 turbo?

The oil feed inlet is on the top, the oil feed outlet is on the flange it’s sitting on and one of the two water supply ports faces the camera. Water cooling the center section is what really made turbocharging practical on passenger cars and light trucks.

Journal bearings are oil-fed plain bronze bearings. June 2009 | MasterTechnician Online

Tu r bochargers Part 2

It’s not uncommon to seize bearings and snap shafts. Look for discoloration and tiny “welded” spots any time you have one apart.

Brains not necessary, apparently), or poor maintenance on the part of the owner. Turbos handle and retain a huge amount of heat, even after shutdown. You must use the correct oil type and viscosity. Many of these engines specify synthetic oils, so pay attention. After the oil change, never rev the engine until oil pressure builds. If you don’t get proper gauge movement, or the engine low-pressure oil light isn’t out in 15 seconds, shut ‘er down and investigate. Even at idle speeds it only takes about thirty 22 MasterTechnician Online | www.mastertechmag.com

seconds to damage the turbocharger bearings. If you rev the engine right after oil change, you might damage the bearings instantly. Don’t do it! If you get a lubrication-related turbo failure and it’s a water-cooled unit make sure the cooling supply in and out is unrestricted and that the cooling system is operating properly. It’s also a good idea to replace the oil supply and return lines at the same time since there have been many instances of these lines coking shut with heat. I’d advise any customers with turbocharged cars to allow 30 seconds of idle time prior to each shutdown after a normal drive cycle. I know it’s a pain, but those few seconds will extend turbo life and save

Tu r bochargers Part 2 them money. I’d also advise customers that if they’ve been out “whuppin’ it up” to allow two or three minutes of cool-down time prior to securing the engine. It’s a small price to pay.

clean, replace it. On diesel engines, remember that whatever you used to clean the charge air cooler cannot be combustible unless you’re willing to risk a runaway engine.

FOD

Weakling?

The second most common failure is foreign object damage (or FOD.) Make sure that during routine service all shop towels, nuts, bolts and wrenches are accounted for prior to startup. Foreign objects may be introduced by others, may fall off the turbo itself – like the nut holding the compressor wheel on the shaft – or in the case of a severely restricted air filter they may come from the inlet system. A restricted air filter could collapse and shred and become the source of all kinds of debris in the intake tract, and anything that touches either wheel guarantees instant shrapnel. There is no forgiveness if something is ingested into a wheel spinning at 50,000-125,000 rpm. If you have a FOD failure, you’ll need to clean the inlet and charge air cooler to prevent a repeat. If there’s any question about whether the charge air cooler got

Low-power concerns are often assigned to the turbocharger immediately, but that’s not always a good idea. First of all, see if there’s a lot of detonation sensor activity. On late-model turbocharged vehicles, not only will timing be retarded, but boost may be shut off or limited. I’d certainly put a pressure gauge on the intake side, but don’t forget to look at overheating, timing belt/cam timing issues, restricted exhaust systems, fuel pressure and volume and base timing, if adjustable. Don’t step over the obvious to get to the obscure. Once the basics are covered, check waste gate operation. I don’t have a dedicated tester for waste gates, but I do have a radiator pressure tester that I’ve adapted to check the pressure at which the waste gate starts to open. If that’s good, and you’re still not making boost, then you may find

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It doesn’t take a lot to trim off the ends of the blades. Even opening up the relationship between wheel and housing a few thousands will dramatically change the pump efficiency.

of shaft and bearing damage, which should also show up as rub marks on wheels and housings. If you find a compressor or turbine wheel coked or carboned up, it’s okay to clean it, but never with any kind of metal object, including a wire brush. The slightest scoring on the wheel will create a stress riser that will lead to a burst wheel. Soft bristled brushes and solvent only, please.

yourself pulling the turbo off to examine the wheels and shaft, which is not always a pleasant job. If you have to pull the turbo, now’s the time to check for oil in the intake manifold after the turbo, and the exhaust system ahead of the turbine and after. Even if you don’t have oil consumption complaints, remember that most people don’t check their oil and that catalytic converters may “eat” the oil smoke. Some turbos use a mechanical oil seal, some use a labyrinth seal and others rely on the high shaft speed combined with dams and diverters to sling the oil away from the area where the shaft passes through to the wheel. In most cases, oil consumption will be the result

The gas/oil seal is a simple metal part resembling a piston ring.

Once removed, examine the compressor wheel, turbine wheel and their respective housings for signs of damage or rubbing. Using a bright light, take a careful look at the compressor wheel. It should not have a sandblasted or “softened edges” appearance. If it does, it may have been damaged by running without an

June 2009 | MasterTechnician Online

Tu r bochargers Part 2 air filter. Turn the turbo by hand. It should spin freely with no scraping or rubbing. Next, push in on one of the wheels and turn it by hand. Again, there should be no rubbing. Finally, push in on the other wheel and turn it by hand and check for rubbing. Any failure that changes the shape of the wheel or the contour bore renders the turbo useless. One last failure to mention: overboost. If there is a waste gate or VNT system failure, you could end up with more intake pressure than the engine was designed to handle. In many cases, overboost is the result of an overzealous owner bolting on power-up parts to gain that extra edge when he and his buddies are out drag racing their three-quarter ton pickups in the country (Hey! I’m a Hoosier, remember? I never said I was sophisticated!) Okay, here’s the story. I won’t say who was involved in this, but I have intimate knowledge of a certain middle-aged fellow who once owned a GMC Syclone turbocharged pickup truck.

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It’s pretty obvious what we’re doing here. If you open the gate, the exhaust gases bypass the turbine wheel, slowing shaft speed.

Said middle-aged crazy individual expressed a need for more speed, and mysteriously an extra “tee” appeared in the wastegate line and said line was terminated with a carburetor jet as a calibrated air leak. Seems that the computer control system was smart enough to shut the fuel off in the event of gross overboost (and you haven’t experienced something lying down hard until you hit fuel shutoff on a turbocharged engine that’s building boost like an Atlas 5 launch vehicle – you’ll leave teeth marks in the steering wheel), but not smart enough to detect, say, 2.5-3.0 psi of extra intake pressure. After a good

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Tu r bochargers Part 2

A non-removable backplate rebuilt Holset turbocharger.

many fun Fridays nights laying waste to members of the local street-racing crowd, the truck appeared one day with a rather annoying ticking sound going on in the engine. On further investigation, it was determined that the noise was low, and seemed to be at crankshaft cadence. On teardown, we discovered that one connecting rod was twisted about 8-10 degrees, and shortened just enough for the

28 MasterTechnician Online | www.mastertechmag.com

pin boss to hit the counterweight of the crankshaft as the piston swung through bottom dead center. Now THAT is cutting it pretty close! Moral of the story? If you get complaints of sudden violent shut down, or if you see overboost occurring during your diagnosis, remember there may be some other clown like that (moi?) out there trying to get that extra little edge by modifying the boost map.

Finding replacments Turbochargers aren’t really that complicated. For the most part, they are no longer field-serviceable, and repairs are confined to replacement AND making sure that the root cause of failure is identified – nothing is worse than calling your supplier with a “defective part” only to find that the swarf from the last failure clobbered your new unit. In my case, I’d see our friends at Fort Wayne Diesel for remanufactured replacement turbos (and they have other

locations; check the website below), but Googling “remanufactured turbocharger” brought up dozens of potential suppliers. Depending on the application and mileage, having a good reman supplier could save you and your customers a lot of time and money. The majority of remanufactured units out there are probably going to have a new center housing rotating assembly with used compressor and turbine housings around it, so service life should be good. Keep it oiled, keep it cooled, and keep debris out and you and your customer will be happy.

Special thanks to Pat Kiel of Fort Wayne Diesel (part of Diesel Injection Service Company - http://www.dieselusa.com/) for several hours of help. Pat donated three boxes of parts and pieces, new and used for my use over a weekend to get this story done. I would also like to thank an extraordinarily professional group of people at Garrett Turbo (http://www/turbobygarrett.com), including Kyle Snyder and Craig Gibbs for sending us photos and answering some very technical questions on short notice. Check out their website for more technical information about turbocharging. If these guys don’t know it, it isn’t worth knowing!

June 2009 | MasterTechnician Online

o diagnose any system, you need to understand how it works. For this article, weâ&#x20AC;&#x2122;ll assume you know the basic principles of ABS so we can move right to exploring the particulars of the Teves Mark IV system and looking at some of its common problems.

Trio There are three major components starting with the electronic control module, which Chrysler refers to as

30 MasterTechnician Online | www.mastertechmag.com

a CAB (Controller Anti-Lock Brake). This monitors the wheel speed sensors along with other inputs, and controls the ABS hydraulic valve unit, the next component. This houses all of the isolation and decay solenoids (four of each). Finally, we have the ABS pump motors, which create the hydraulic pressure needed to reapply the brakes during an ABS stop. There are two motors and two accumulators, one set for each brake circuit. The pumps donâ&#x20AC;&#x2122;t have their own electrical connector and power supply relay, but are connected to the

Brainpower The ABS control unit is mounted underneath the driver’s side of the dash to the right of the brake pedal. It gets power input directly from the ignition switch. Once it sees that the ignition is on, it grounds the ABS main relay, which is mounted in the junction block -- that is, the fuse box underneath the dash on the left side of the steering column. The relay is in position #7. If you look at the wiring diagram, you’ll see that once This is the power distribution center. It houses the ABS pump motor relay, the light grey one in the middle of the box on the right. Since this relay is separate from the CAB and the hydraulic valve unit, we can test it for causing a pump motor failure message.

hydraulic valve unit and are serviced together. Unlike other manufacturers, the pump motor relay is mounted in the power distribution center and is not part of the motor or the hydraulic valve unit. So, that pump motor or relay circuit code does not necessarily mean you have to replace the whole ABS hydraulic assembly.

Here’s the ABS control unit or the CAB. You can remove the black connector cover and perform most of your electrical tests right here providing you can stand being wedged underneath the dash. June 2009 | MasterTechnician Online

Tr i mming the ABS . . .

This is the junction block, which houses the ABS main relay (top row, second from the right, half hiding behind the diagnostic connector). You should hear this relay click when you turn the ignition key on.

the relay is turned on the power from fuse #17 in the power distribution center is sent to pin #87A of the relay and leaves by way of pin #30. This supplies voltage to the ABS hydraulic valves and back to the power distribution center to power up the control circuit of the ABS pump relay. It also supplies voltage to a separate pin on the CAB to verify the relay is activated, and provides voltage to the hydraulic valves as well as to the Message Center. This voltage to the Message Center prevents the ABS warning light from being turned

32 MasterTechnician Online | www.mastertechmag.com

Click to enlarge.

In this diagram we have the wiring diagram for the ABS Main Relay. Use this diagram to follow along with the explanation of how it provides power to the Hydraulic Valve unit and controls the ABS light.

on. If the relay is not energized, the circuit remains grounded by the main relay and the control unit grounds the wire that turns on the ASB light. A diode is wired into the junction block to prevent the voltage from the Message Center from being grounded by the hydraulic valves or the pump relay. We know it sounds confusing in words, but if you read it over with the wiring diagram in front of you it does make sense.

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Tr i mming the ABS . . .

Here’s the socket for the ABS pump relay. Pin #86 is the slot the farthest to the right, parallel to the right edge of the PDC. With the ignition key turned on, this pin should have battery voltage.

ABS relay and check for voltage at terminal #86 of the ABS pump relay. Now that we have our control unit powered up, let’s review the inputs it will use in an ABS stop. Of course, there are the signals from the brake switch and the wheel speed sensors. The brake light switch input also doubles as the brake light switch, so unless you have a bad splice, a quick stab at the brakes should let you know if the switch is working. The wheel speed sensors are AC pulse generators, so if you scope them you’ll see an AC waveform. Also, they should have about 900 to 1300 ohms of resistance.

So, we’ve talked about the CAB’s power supply, but what about its ground? That’s handled by two wires found in the passenger side kick panel, which are part of a ground block with multiple wires.

How do I test it? At least now we know that the main relay not only powers up the system, but controls the ABS light as well. The fastest way to see if the relay is working properly is to unplug the 34 MasterTechnician Online | www.mastertechmag.com

It’s difficult to get to the connector for the passenger side front wheel speed sensor and unplug it.

properly. If the scope pattern looks good and the resistance is within specs, one problem often overlooked is RFI. Check if any high-current wires are running near the speed sensor wiring. The sensors use twisted pair wires to reduce interference, but high current loads can still induce a code.

Here’s the other side of the wheel speed sensor connector. The best way to get at it is to remove the 10mm bolt holding down the retaining bracket and pull the sensor through the hole. You’ll find you have much more room to work.

Watch out for cracked tone rings, which may give you low speed activation of the ABS for no reason. Also, check if the vehicle has had the axles replaced because he wrong number of teeth on the replacement will throw off the ABS. If your scan tool is capable of talking to the CAB module, you’re in luck. You can monitor the wheel speed sensors in data and see which one is setting the code or not reading

A problem that may come up is “No Communication” with the CAB module. Keep in mind the CAB is on a CAN (Controller Area Network) and any of the other control units on the CAN may bring down communications. First, try to talk to other control units on the CAN and see who’s talking back. Another way to test the CAB through the CAN is to unplug each control unit on the CAN until you can start talking to the CAB. You may find that when you unplug the CAB you can talk to the other control units. This would indicate a bad CAB, or a loose power or ground supply. One important item to know is that the red brake warning light does not have an input to the ABS control unit, so the hydraulic portion of the brake system will not turn on the ABS light and visa versa.

June 2009 | MasterTechnician Online

Tr i mming the ABS . . .

What about the hydraulic part? What does the brain do with those inputs? During an ABS stop, depending on which wheel(s) is locking up, the CAB module will ground any or all of the four isolation and the four decay solenoids to apply and reduce brake pressure to the individual calipers. As we said, the hydraulic unit also houses the ABS pump motor and accumulators, which make and store hydraulic pressure for an ABS stop.

The hydraulic valve unit and pump motor assembly is mounted underneath the vehicle, which makes R&R fairly easy. Notice the lettering stamped on the aluminum bracket outlining the four different brake circuits. 36 MasterTechnician Online | www.mastertechmag.com

The hydraulic valves are supplied voltage with the key on. To check the solenoids and wiring, all you have to do is check the eight pins at the CAB for battery voltage. Keep in mind that you must have the CAB module plugged in -- otherwise, the ABS main relay will not be energized. The solenoids should have about 5 to 9 ohms each. The hydraulic valve assembly is mounted under the van, but you can check resistance without putting the vehicle on a lift. Measure between terminal #30 of the ABS main relay and each of the eight pins on the CAB. If you just want to bleed the system after a brake job, or for maintenance, you can bleed them like conventional brakes. Start off with the left rear wheel followed by the right front, then the right rear wheel followed by the left front. If you’re replacing the ABS hydraulic valve unit, however, you will need a scan tool capable of the “Bleed ABS” routine. This will activate the solenoids while the brake pedal is applied and purge the hydraulic assembly of any air. For those of you without this type of scan tool, you

Tr i mming the ABS . . . can carefully drive the vehicle in an empty area with no traffic and perform some ABS stops. This will cycle the air out of the system as the ABS solenoids energize. However, this is time-consuming -- you may have to go out and drive it four or five times and bleed it after each road test. So, itâ&#x20AC;&#x2122;s not recommended, but it may get you out of a pinch.

Under pressure! Although the ABS pump motor is part of the hydraulic assembly, there are other parts to check before replacing it. We mentioned earlier that the ABS pump motor relay is mounted in the Power Distribution Center on the right side, the fifth relay from the bottom of the box. It gets voltage from maxi-fuse #7 in the same box on terminal #30 of the relay. This relay is only activated by the CAB when the ignition is turned on and during an ABS stop. You could jump pins #30 and #87 and provide power to the pump motor, but only for a few seconds. These motors were not designed to run for very long and [8] testing like this may damage the pump. The pump should draw 3.5 to 38 MasterTechnician Online | www.mastertechmag.com

4.0 amps. Any more than that and it may be on the way out. You do have to make sure that you have a good power supply to the pump. If the voltage is too low, the amp draw will read abnormally high and you may believe the hydraulic assembly needs to be replaced. The high pump current draw will cause the ABS (Below) You can monitor the amperage draw of the motor by jumping terminals #30 and #87. This unit settled down at about 3.8 amps.

This is a scope pattern of the voltage and current of the ABS pump motor. Notice that when Trace A goes up to approximately 12 volts, the amperage â&#x20AC;&#x153;inrushâ&#x20AC;? peaks at over 40 amps (the current probe is set at 100mv/amp), but then settles down to about four amps, which is what we tested earlier.

June 2009 | MasterTechnician Online

Tr i mming the ABS . . . light to come on. Unplug the pump and activate the relay. You should only see .1 of a volt drop from fuse #7 to the power supply to the pump. You can also leave the pump motor plugged in and measure the voltage to the pump while energizing the relay, but, again, only for a few seconds. One of the reasons we stress voltage drop testing is that since the relay is mounted in the Power Distribution Center corrosion can build up in the wiring under the PDC -- we’ve seen copper oxide on the pins of the relays where the wires connect. This can lead to voltage drop and failure of electrical components, including the ABS pump motor. This is just another problem to watch out for so that expensive parts are not replaced for no good reason. Ditto for the ground side.

You have a code? We mentioned using a scan-tool to pull codes, but this is not entirely true. Chrysler does not use numeric trouble codes to identify the problem in its self-diagnostic check. Instead, we just get the description. Your best bet

40 MasterTechnician Online | www.mastertechmag.com

is to match the scan tool’s description with Chrysler’s description and follow that flow-chart. Oh, we forgot: Chrysler doesn’t call them flowcharts. They’re diagnostic charts or test charts or whatever else the company wants to call them. The chart numbers range from Test 1A to 22A. Once again, match the scan tool description with the test chart description and you should be on the right path to fixing this “code”. Also, keep in mind that when a CAB module gets replaced on later models it must be programmed with info on wheel and tires size, as well as engine and transmission. Be prepared. These vans are getting older, but we still work on a lot of them. Keeping the ABS system functioning, even on a 10 year-old-vehicle, will keep your customers coming back, whereas the purchase of new minivan may have them going to a dealer for a few years. A fast and accurate diagnosis will save you time and the customer money, making the vehicle more cost-effective to keep, and it’ll still be a safe ride. What could be better?

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Make Before Break -Measuring Parasitic Currents by Wade Nelson The rule of thumb is, “Anything under 30mA is acceptable, anything over 50mA indicates an excessive draw.”

etermining the reason a battery keeps going dead includes testing for parasitic draws. The rule of thumb is, “Anything under 30mA is acceptable, anything over 50mA indicates an excessive draw.” The greatest difficulties in measuring parasitic draws are mostly practical matters. Having a third hand would make taking a parasitic draw measurement much easier. Mistakes are easy to make, like inadvertently opening a car door, or leaving the keys in the 42 MasterTechnician Online | www.mastertechmag.com

ignition. The first will blow the fuse in your DMM, the second will give you an incorrect reading. Here are some tips and tools to make parasitic draw testing faster, easier, and perhaps save you a few meter fuses. The primary difficulty in making a parasitic draw measurement lies in establishing the “shunt” connection through your ammeter (DMM) prior to disconnecting the terminal from the battery post, without accidentally breaking that shunt connection

while removing the terminal from the battery post. It absolutely has to be a â&#x20AC;&#x153;make-before-breakâ&#x20AC;? transfer to avoid sending one or more modules back into an initialization process. Having a co-worker help you set up the test leads on a parasitic draw measurement is the fastest method of getting the job done. Several commercially available test adaptors will allow you to accomplish the task solo including the Kent Moore J38568 and OTC 7645, or you can home-brew an adaptor.

Commercially available parasitic draw test adaptor.

(Below) Nobody likes blowing DMM fuses.

June 2009 | MasterTechnician Online

M e asuring Parasitic Curr e n t s One eBay vendor, “A-fluke,” offers a parasitic draw tester, similar to an OTC7645, but with test leads already attached. If you were to cut one of the two leads, and insert a 10A blade fuse holder or circuit breaker, you’d have an almost perfect tool for parasitic draw testing – one that would prevent you from ever again blowing an expensive meter fuse. An inductive DMM eliminates connection problems, but simply can’t read as small a current as an ammeter in series.

44 MasterTechnician Online | www.mastertechmag.com

As with all measurements of electrical current, you sever the circuit, and insert your ammeter inline between the two severed ends. But in this case, you can’t ever allow the two ends to become completely electrically disconnected. Current must always be able to flow, either through the battery cable itself, or “shunted” through your DMM. If the circuit gets completely opened and you re-connect the leads, one or modules in the vehicle will go into an initialization routine, boosting

current flow considerably. This may or may not blow your meter fuse, but it will definitely give you an incorrect reading. You have to wait until that process completes and they are ready to go to sleep before you can try again. On some vehicles, you can use a scan tool to command modules to quickly go to sleep, which is a time-saver

Calibration Run

it then decreases to 17 milliamperes. You may need to change the range on your DMM, perhaps even which jacks the probes are plugged into to accommodate measuring such a wide range of current levels. Since changing the jacks, or even switching the range, can momentarily break the circuit, you may need to plan ahead, and NOT insert your DMM into the circuit until an appropriate time.

You need to determine what amperage range the parasitic draw is in immediately after the ignition is turned off, and approximately how long it takes before the vehicle goes to sleep. It could be 45 seconds, or 15 minutes on different vehicles. Baseline information from testing similar vehicles can be invaluable, and save you time on a “problem” vehicle.

Pre-Test

Suppose that for 30 seconds after ignition off, you’ve got a current draw of 2.2 amps, or 2200 milliamps. After 45 seconds it goes down to .12A, or 120mA. After five minutes

Be sure to unplug any accessories from the cigarette lighter outlet and any accessory outlets in the rear of the vehicle. Most importantly, remove the keys from the ignition.

GM’s parasitic draw test procedure recommends road testing the vehicle and activating ALL electrical accessories, including the radio and air conditioning prior to parking, turning the ignition switch to the OFF position and removing the key. With today’s feature-laden cars, that can be a lot of button pressing.

June 2009 | MasterTechnician Online

M e asuring Parasitic Curr e n t s Otherwise, some systems may stay powered-up. Consider the effect on the factory security system of having the hood up. Look for hood switches, and defeat them. Unhook any underhood trouble lamps. If having the hood up doesnâ&#x20AC;&#x2122;t prevent its use, use the remote (key fob) to lock the vehicle, just as you would if you were leaving it in a parking lot. Make sure all doors and hatches are shut.

Get all your clips, clamps, etc. together before you start.

46 MasterTechnician Online | www.mastertechmag.com

Get Ready: The most time-consuming mistake you can make is starting the measurement process with the fuse in your meter already blown. Test it beforehand by measuring the current through an #1156 tail lamp bulb set on one of the battery terminals, using your meter leads to form the other connection. It should read approximately 1.6 amps. Have some

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M e asuring Parasitic Curr e n t s extra meter fuses available in case you screw up. Courtesy lamps alone may not pull more than 10A, but other onboard systems may “wake up” if a door is inadvertently opened, immediately putting the shunted draw over your meter’s fuse limit. Second, have all the alligator clips and jumpers you could possibly need, including perhaps some battery charging clips or side post adapters,

so after getting everything hooked up you can set your meter down and walk away. Having to stand there and firmly press a DMM probe into a lead battery terminal gets very old after very few minutes, especially the third or fourth time you do it! This is where a DMM with min/max recording ability proves its value, since you can walk away, and come back anywhere from 10-30 minutes later and hit the button to see the value.

Since you can’t simply pull a fuse for the alternator if you suspect it’s the cause of the draw, simply disconnect it.

48 MasterTechnician Online | www.mastertechmag.com

Parasitic Measurement Gotchas: The auto manufacturers seem to be intent on making parasitic draw measurements ever more difficult to make. Here are some of the “land mines” they’ve left behind: •Reportedly, some Chryslers are programmed to burn off the MAF sensor wire in the middle of the night, causing a noticeable increase in current – several amps. A similar report claims some Chryslers test 02 sensor heaters at oh-dark twenty. •NVLD (Natural Vacuum Leak Detection) can run on GMs for up to 45 minutes after Key Off. •Toyota’s EVAP pump can run for 10-12 minutes starting five hours after the engine is turned off. •On Ford Escape hybrids, the antilock brake system reportedly does a self-test with the key off. But when?

•Boomerang 1 [theft recovery] devices draw between 35 and 55 mA. Boomerang 2 units “lay low” for 15 minutes when power is removed. Details on LoJack current draws aren’t available. •Some GM regulated voltage control (RVC) systems are designed to wakeup, perform a task, and fall back to sleep at regular intervals. •OnStar will create draws for the first 48 hours after turning the ignition off. The system will cycle every 10 minutes and spike to 250 mA for about ten seconds, taper down to 75 mA for another 45 seconds and go to less than 1 mA until the next cycle begins. This cycle stops if power is removed from the OnStar system for a short period and will resume once a GPS signal is reacquired. •Some Chevy Dual Zone Automatic A/C systems were designed to “stay awake” for up to four hours after the ignition is turned off. •As always, check for TSBs.

June 2009 | MasterTechnician Online

M e asuring Parasitic Curr e n t s

The “Usual Suspects” When a vehicle has an unacceptable amount of parasitic current drain, remove one fuse at a time until the current drain falls to an acceptable level. This will indicate which circuit is causing the drain. If pulling a fuse eliminates a parasitic draw, refer to the vehicle’s power distribution schematics to determine which circuits are fed by this fuse. Careful – you can’t just open the door to get to an in-cabin fusebox!

50 MasterTechnician Online | www.mastertechmag.com

Using 30mA as a baseline, you can sometimes use the amount of excessive parasitic draw to help refine your guesses as to what may be causing it. For example, is there enough additional drain to suspect a light bulb is illuminated somewhere? Beware of non-fused circuits. A failed diode on an alternator can cause a parasitic draw that pulling fuses won’t reveal. Some relay circuits may

Any non-O.E. add-on should be suspect, especially amps and alarm systems.

not be fused. Improperly installed audio amplifiers staying powered up all night long are some of the most common causes of parasitic draws. You’ll often see the power leads for “suspect” systems “MacGuyvered” directly to the battery terminals. Before you pull a single fuse, unhook these bad boys and re-check the parasitic current levels.

Future of Parasitic Draw Testing The future of parasitic draw testing is either very dim or very bright, depending on how you look at it. The latest BMWs and Toyotas and most hybrids incorporate a sensitive battery current monitor directly on the battery terminal. Combined with the PCM, this is capable of monitoring and recording parasitic draws. All the tech need do is hook up a scan tool and view recorded data. Multiple battery setups can complicate parasitic draw testing. Hybrids aren’t the only vehicles equipped with dual batteries these

days. Others vehicles include the Mercedes McLaren SLR and Lexus 460, and “mild” hybrids like the Chevrolet Silverado. Unlike large trucks and RVs where two or more 12V batteries are simply connected in parallel, various electronics may greatly complicate parasitic testing on these vehicles. Virtually all hybrid “main” batteries incorporate battery current monitoring features, fortunately.

Summary: Parasitic draws are one of the three most common causes of dead batteries. Any parasitic draw over 50mA is suspect. With a little practice making parasitic draw measurements becomes secondhand. The usual suspects in parasitic draw measurements are aftermarket stereos, amplifiers, and security systems. Homebrew or aftermarket adapters help make parasitic draw tests easier. The key technique is a “make-before-break” shunt of battery current through the DMM used to measure parasitic draws.

June 2009 | MasterTechnician Online

Over a million gasoline hybrids are on the road and need service. Are you ready to handle the repair needs of this growing market? In this second of two parts, weâ&#x20AC;&#x2122;ll delve into the components, the technologies, how to service hybrids, and where to find training programs and resources. (Image Courtesy Cadillac.)

n the first part of this article, we looked at the history and development of gasoline engine/ electric motor hybrids, how they function and which vehicles employ hybrid drive systems. In this second part, weâ&#x20AC;&#x2122;ll explore hybrid technology, the service aspects and where you can procure training 52 MasterTechnician Online | www.mastertechmag.com

and resources for launching into hybrid service and repair. The basic message is that you can service hybrids and need to be knowledgeable about how they operate, how to diagnose them, and skilled in repair techniques â&#x20AC;&#x201C; if you want to be competitive.

Components & technology The components that set hybrids apart from standard I.C. engineonly vehicles are the high-voltage generation, drive, control and storage devices. Some of these components range from 144-650 volts and should be considered lethal. They are indicated by bright orange wiring and harness covers. Never attempt service on these components unless you are properly trained and experienced in the technology. Always refer to the specific service information for the vehicle you are servicing. In most cases, malfunctioning or failed electric and electronic components are simply removed and replaced, with the exception of some control modules, which can be re-programmed. Here are some generic descriptions of these components found on hybrid vehicles:

Motors The electric drive motors used in hybrids are high-torque heavy-duty permanent magnet motors. These

compact, but powerful, dynamos operate on power raging up to about 650 volts. Many also serve as generators to create electrical current to recharge the batteries or power the vehicle directly.

Powerful motors, such as this one in the Honda Civic, drive the vehicle and generate current to recharge the battery pack. (courtesy Honda)

Starter/Generators These dual-purpose motors are referred to by vehicle manufacturers by different names. An Integrated Starter Alternator (ISA), or Integrated Starter Generator (ISG), is built, or integrated, into the existing hybrid structure, rather than hung on the engine as an accessory. The Flywheel Starter Alternator (FSA) found on GM pickups is an example.

June 2009 | MasterTechnician Online

A r e you ready for the H y b r i d H i g h w a y ? Whatâ&#x20AC;&#x2122;s called a Belt Alternator Starter (BAS), however, is usually mounted on the engine like a standard belt-driven alternator. Presently, only GM uses BAS-type starter/generators. A good example is the Malibu Hybrid.

Inverters

Converters

Regenerative braking technology

Converters (DC-to-DC) alter voltage up or down as needed for various components. This may require changing the battery voltage â&#x20AC;&#x201C; which may range from 144V to 488V â&#x20AC;&#x201C; to as low as 12V to power the lights, accessories and convenience systems, or step it up to as high as 650V to power drive motors.

DC-to-DC converters change the voltage level for various uses in a hybrid system. (courtesy Denso)

54 MasterTechnician Online | www.mastertechmag.com

Inverters convert DC to AC for the purpose of driving AC motors or other devices, as well as to power 120V outlets to run convenience items such as power tools, or household appliances.

Regenerative braking allows a motor to act as a generator when coasting or braking. Kinetic energy that normally would be wasted during braking is converted into electrical energy to recharge the battery.

Inverters change DC current to AC flow for powering AC motors, or provide 120V AC current outlets. (courtesy Toyota)

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A r e you ready for the H y b r i d H i g h w a y ? The energy conversion is not achieved by producing waste heat in the pads and rotors as in traditional braking systems, but within the integrated motor/generator units. While the brake pads and rotors stop the wheels at high speed or in emergency situations, the regenerative braking system slows the vehicle in normal driving. Regenerative braking takes place when the foot is lifted from the accelerator pedal, or the driver applies

the brake pedal. To visualize this effect, think of the engine braking and drag experienced when you downshift with a manual transmission. An important note on brake service: Since the regular hydraulic service brakes on hybrids get little use in normal driving, especially around town, the calipers and rotors can rust to an extent that youâ&#x20AC;&#x2122;ve never seen before. So, every time youâ&#x20AC;&#x2122;ve got any hybrid on the lift, do a thorough

A monitor screen on this 2007 Toyota Camry Hybrid continually displays the hybrid operation and function, including the level of regenerated power (Courtesy Toyota). 56 MasterTechnician Online | www.mastertechmag.com

brake inspection. Clean, lubricate, or replace components that exhibit advanced corrosion to keep you customer safe

Electric A/C compressors Electrically-driven air conditioning compressors allow cabin cooling to continue when the engine is stopped. Also, they donâ&#x20AC;&#x2122;t rob the engine of energy, as with conventional systems, and therefore reduce fuel usage and improve mileage.

Electric-powered A/C compressors provide cabin cooling when the gasoline engine is not running (courtesy Denso).

Batteries Hybrid battery packs often have their own dedicated control units, monitoring systems and cooling systems. All current (no pun intended) hybrids use nickel metal hydride (NiMH) battery packs. These packs consist of many small, D-size, 1.2-volt cells connected together. The number of cells, therefore, determines the total voltage of the battery pack. For example, the Toyota Prius combined 228 cells for its 2001-2003 273.6-volt battery pack.

Hybrid high-voltage battery packs are usually located toward the rear of the vehicle for weight distribution, under the rear seat in this Lexus RX 400h (Courtesy Lexus).

June 2009 | MasterTechnician Online

A r e you ready for the H y b r i d H i g h w a y ?

Yes, you can fix hybrids Right about now, you’re probably wondering if you’ll be able to service a hybrid when one rolls into your shop, or if you’ll have to turn it away. The answer is: Yes, you can service hybrids – with some basic understanding and common sense.

A hybrid vehicle, after all, is really just a car with a high-voltage battery, some sophisticated controls and one or more powerful electric motors. The rest of the vehicle consists of components and systems with which you’re already familiar. Every hybrid has the same OBD II diagnostic system and data link connector found on non-hybrid

This underhood photo of a Honda Accord clearly shows the bright orange high-voltage system harness. NEVER probe this harness or the connectors (Courtesy Honda). 58 MasterTechnician Online | www.mastertechmag.com

vehicles, so you can easily connect a scan tool and read codes. Just as you would with any type of vehicle you’ve never serviced, take the time to read the owner’s manual, log onto your service information provider’s system, and/or visit the manufacturer’s technical information website to educate yourself about the vehicle before beginning work. Better, you should gain some knowledge and a little practical experience working on hybrids if you plan to make them part of your business. Taking a class in hybrid service is strongly recommended for a full working knowledge of hybrids. That being said, let’s cover some important factors you should keep in mind when servicing hybrids.

Safety first! No kidding You’re going to be working around very high voltage. Always take proper precautions. 1. NEVER – under any circumstances – probe the bright orange highvoltage system harness or connectors.

2. ALWAYS shut the high-voltage system down when working anywhere near a hybrid system-related component. The shut-off switch can be located by reading the owner’s manual. It may be in the trunk, behind the rear seat, or elsewhere. Be sure to wait the appropriate 5-10 minutes after flipping the switch for the system’s capacitors to discharge. Refer to the correct service information for specific details. 3. BE SURE to remove the key from the ignition and make sure the vehicle is in park before working around the accelerator. On models that incorporate a proximity key system that doesn’t require the insertion of a key, only that the fob transmitter is within a certain range before the START button is pushed, make sure the fob is out of range. Examples include later models of Toyota or Lexus vehicles. 4. ALWAYS educate yourself about the intricacies of the specific vehicle you intend to service, just as you would any other vehicle. Access the correct service information from your service information provider, or log onto the manufacturer’s technical information website.

June 2009 | MasterTechnician Online

A r e you ready for the H y b r i d H i g h w a y ?

Manufacturer technical information websites For basic maintenance and service information, you can access your regular service information provider, but most donâ&#x20AC;&#x2122;t include detailed information on hybrid components and specifications. The best sources for hybrid diagnostics, repair and parts information are the technical information websites of the vehicle manufacturers. Each, of course, requires a fee for use. These websites may be accessed through the National Automotive Service Task Force (NASTF) website at www.nastf.org, or individually as listed below:

Chrysler

www.techauthority.com

Ford

www.motorcraft.com

GM (Chevrolet, GMC, Saturn)

Hybrid system parts Because there are no aftermarket sources yet, all new or remanufactured hybrid components must be purchased through OE dealers. The 2000 EPA mandate and the NASTF agreement ensure that every automobile manufacturer will make parts, tools and service information available to aftermarket service sources.

Special tools Special tools for servicing hybrid components are also available under the NASTF ruling by visiting the OE websites listed above. In most cases, you do not have to log onto the website, thereby incurring a fee, to access the tool source information.

www.gmtechinfo.com

Honda

www.ServiceExpress.Honda.com

Mazda

www.mazdatechinfo.com

Nissan

www.nissantechinfo.com

Toyota

www.techinfo.toyota.com

60 MasterTechnician Online | www.mastertechmag.com

Hybrid training courses Auto Career Development Center (ACDC) Craig Van Batenburgâ&#x20AC;&#x2122;s popular multi-day in-depth hybrid classes are available for technician groups on

ven before 1900, vehicles powered by electric motors and gasoline engines were developed and sold to the public. In 1898, carriage maker Jacob Lohner & Co in Vienna, Austria asked employee Ferdinand Porsche to create drive system that incorporated both electrical and gasoline engine propulsion.

The 1898 LohnerPorsche is considered to be the first successful electric/gasoline hybrid

Porsche’s series hybrid system fitted a motor to each of the front drive wheels. A gasoline engine powered a generator to power the motors. Porsche proved the system himself by driving prototype vehicles to several European speed records and won a few races. Over 300 of the Lohner-Porsche “hybrids” were sold to buyers from 1901 to 1906, before the competition from lower-priced gasoline-only vehicles eliminated them from the scene. Over the next few decades, other gasoline/electric vehicles entered the marketplace; only to meet the same fate (courtesy National Automotive History Archives).

request, or are regularly scheduled at various locations. He also has several books and manuals on the subject of servicing hybrids. Check the website or call for more information. www.auto-careers.org 800-939-7909 CARQUEST The CARQUEST Technical Institute occasionally offers classes in hybrid maintenance, generic hybrid service and specialized Toyota THS and HSD system diagnosis. These are eight-hour sessions taught at various locations around the country. Check the website, or ask your local CARQUEST provider for specifics. www.carquest.com June 2009 | MasterTechnician Online

by Tom Nash

The really big deal that never happened. What caused these proposed high voltage systems to fizzle out?

few years ago, we were told that all vehicles produced worldwide would be equipped with 36/42-volt electrical systems by the end of this decade. It isn’t going to happen – not for a long time, at least. It may eventually come to fruition, but a lot more research, development and industry cooperation will be needed. The big question at this juncture: Is it needed?

62 MasterTechnician Online | www.mastertechmag.com

It all started in the mid-‘80s, when automotive engineers – mostly in Germany – were concerned about the ability of electrical systems to handle all the technicallyadvanced components slated to be included in automobiles of the future. The addition of passenger convenience, safety, infotainment and communications systems, and onboard interactive control and regulating modules would require big increases in electrical capacity.

Big Drag Another big consideration was engine efficiency. The amount of energy needed to drive auxiliary systems – such as the AC compressor, power steering pump, water pump, etc. – drags down the efficiency of the engine. It was foretold that the savings in fuel realized by the changeover to electrically-powered components could run as high as 20%. As a result of this reduction in fuel burned, we were told, emissions would be lowered and the environment would benefit. Engine compartment packaging was another justification. Just think, you wouldn’t have to have all those accessories hanging off the front of the engine and being driven by a bulky belt/pulley/tensioner system. Instead, you could mount them pretty much anywhere you wanted. This could also be a boon to serviceability. How about a water pump wide open on the fender apron?

More efficient, lightweight electrically-driven, electronicallyactuated and controlled systems (called mechatronics) were being developed, including drive-by-wire throttle, power steering, brakes, suspension, electronically-controlled electrically-powered valves, electric cooling fans, coolant (water) and oil pumps, to name a few. These components and systems, some already in use, provide better dependability, suffer less wear and serve to reduce weight, all the while not stealing energy from the engine. Addressing the on-board energy crisis and achieving the efficiency, packaging and mechatronics benefits would be easy, according to the experts, with elevated electrical architecture. It all sounded ideal and relatively simple for the industry to change to a higher operating voltage with commensurate amperage and wattage. While it sounded good in theory, it didn’t quite work out as expected. Many, many factors led to the delay and possibly long-term postponement of the 36/42-volt parade.

June 2009 | MasterTechnician Online

W h at Happened to the 4 2 V S y s t e m ?

What’s a 36/42Volt System? First, let’s clarify what is meant by 36/42 volts. The present automotive electrical architecture is actually 14 volts, as you know. We all refer to it as a “12 volt” system because the battery has six 2.1 volt cells for a total of 12.6 volts, which charges just right at 14 V. A more accurate name would probably be the “12/14 volt” system. Triple that and you’ve got 36/42. When automotive engineers began looking for a higher system voltage to establish as a standard, they wanted to raise the level as high as possible, but not so high as to create a shock danger to humans. Mercedes-Benz is credited as being the first automaker to call for higher voltage systems. An industrywide research consortium was formed, led by the Massachusetts Institute of Technology. The MIT/ Industry Consortium on Advanced Automotive Electrical/Electronic Components and Systems began to address the technical issues of changing over to 36/42 volts. The 64 MasterTechnician Online | www.mastertechmag.com

research was financed by automotive companies, which ponied up $50k each to be part of the consortium. After establishing that human tissue can be damaged at around 56-60 volts (wattage and amperage levels being considered), and assuming that present components could easily be adapted, the architecture point of 36/42 volts was derived. It sounded simple and eminently logical.

Cast of Thousands The first entities to get on board would be the planning, standards and regulation associations, organizations and societies. In Europe, automakers and suppliers formed a working group known as “Fourum Bordnetz” to create standards for the Eurobased International Organization of Standardization (ISO). On this side of the pond,the Society of Automotive Engineers (SAE) became the leader in gathering and sorting out the various methods, devices and knowledge for development of standards. Working with the top engineers from international

companies and organizations, SAE began to call for technical papers and form committees to set standards. The foremost vehicle manufacturers to become involved â&#x20AC;&#x201C; because they had the largest portions of the global market and the biggest At the turn of the century, GM showed off its futuristic AUTOnomy hydrogen fuel cell concept. The skateboard-like chassis contained the fuel cell, and all control systems were powered by 36/42-volt architecture. Production of the changeable-bodied vehicle was projected for 2008 (courtesy GM).

technical budgets â&#x20AC;&#x201C; were BMW, DaimlerChrysler, GM, Fiat, Ford, Honda, Peugeot /Citroen, Renault / Nissan, Toyota, and VW/Audi. BMW, GM, Ford and DaimlerChrysler all boasted that they would have 36/42-volt systems on the road by 2003 or 2004. GM showed its AUTOnomy fuel cell concept equipped with a 36/42-volt system and promised to produce everyday drivers with similar systems by 2007. Ford pledged to have a hybrid Escape with 36/42 volts on the road in 2004 also.

June 2009 | MasterTechnician Online

W h at Happened to the 4 2 V S y s t e m ? These companies began laying out their plans for integrating 36/42volt systems and working with their main component suppliers. Among these highly-reputable suppliers were Aisin, Bosch, Continental Teves, Delco Remy America, Delphi, Denso, Johnson Controls, Lear, Magneti Marelli, Motorola, Valeo,

VDO Siemens, Visteon, Yazaki and a host of others. They were drawn into the creation of high-voltage systems and began expensive research and development initiatives. Many of the products these suppliers created for 36/42-volt systems still sit in inventory, waiting for buyers.

Five years ago, Ford Motor Company was still planning on producing 36/42-volt vehicles within a few years. This is a cutaway view of the proposed 2004 Explorer AWD with a 42-volt Integrated Starter-Generator (ISG) and electrical system (courtesy Ford).

66 MasterTechnician Online | www.mastertechmag.com

integrated starter generator (ISG)

battery electronic control unit (ECU)

DC-DC converter

Denso developed many components for 36/42-volt vehicles including (Left to Right) an integrated starter generator (ISG), a battery electronic control unit (ECU) and a DC-DC converter. (courtesy Denso)

Implementation Imagination The steps in implementation were to have followed this pattern: •The 36/42-volt architecture would be initially applied to high-end luxury vehicles where the cost would readily be accepted. The technology would then trickle down to entrylevel vehicles over a few years, once the technologies were perfected and made cost-effective. •The European manufacturers – primarily the German companies – were slated to convert to the new standards first.

•Dual voltage systems were to be used as an interim solution. Until the design and production of 36volt components was perfected, 12volt sub-systems would be used to power devices that have not been redesigned for the higher voltage. This could be achieved by the use of two batteries – one 12-volt and one 36-volt – and coupling them with a DC-to-DC converter, stepping down the electrical pressure to power those components still functioning on 12 volts.

What Went Wrong? There are many reasons why 36/42volt standards have not yet been adopted and produced. The three June 2009 | MasterTechnician Online

W h at Happened to the 4 2 V S y s t e m ?

In anticipation of the planned 36/42-volt vehicle architecture, Robert Bosch created a 42 volt version of its popular alternator design with a peak power output of 4 kilowatts (courtesy Bosch).

main culprits are technical difficulties, corporate political posturing, and, the big one, financial constraints. Technically, many theories that sounded good in the laboratories and think tanks did not work out so well when it came to implementation and mass production. Some problems became bigger obstacles than first thought. Progressing through all the international standard-setting meetings proved difficult because the many parties disagreed on technical details and began to champion ideas

68 MasterTechnician Online | www.mastertechmag.com

that suited their own purposes. European, Asian and North American representatives all wanted to create standards based on their individual technical systems. This campaigning extended to companies that wanted the standards to reflect the use of products and components protected under their own patents. Of course, thereâ&#x20AC;&#x2122;s nothing wrong with trying to protect your own corporate interests and ensure financial growth, but political maneuvering often gets in the way of true progress and bogs down the entire process. One of the biggest factors in the waning efforts to develop 36/42volt vehicles has been money. Each company involved has spent millions to design new components and systems, but those devices sit in limbo at this point. The return on investment hasnâ&#x20AC;&#x2122;t materialized, and may not. The general downward business trend in the automotive market forced companies to look long and hard at how they were spending money. To satisfy the need for profitability, most companies have now turned their R&D dollars toward other emerging technologies such as diesels, hybrids and fuel cells.

Problems, Problems Dr. David J. Perreault, a research Scientist at MIT’s Laboratory for Electromagnetic and Electronic Systems initially led the MIT/ Industry Consortium on Advanced Automotive Electrical/Electronic Components and Systems. Dr. Perreault presented a technical paper and spoke at the Convergence 2000 conference on October 17, in Detroit. He stated that the higher power would allow many new systems to be introduced and many existing systems to work better.

Nicastri exposed the problems with electrical connections under a 36-volt load. He stated that the entire system will have to be redesigned to handle the high voltage. Wires, relays, and connectors will need improvements to function without damage. Arcing of 36-volt current is the primary concern. Unlike 12-volt arcing, which is fairly low in amperage, short in arc length and easily disrupted, the arc in a 36-volt system can be much longer and reach extremely high temperatures – over 4,000 deg. F – posing a dangerous situation.

“It doesn’t sound like it would be that difficult to do,” Dr. Perreault said. “But it turns out that there are several subtle technical problems.” This comment turned out to be somewhat understated.

He demonstrated these arcing problems with a video showing normal and slow motion views of a 36-volt connector under load being disconnected. The resulting arc and flash entirely disintegrated the tip of the male connector. The female end was badly damaged and unusable.

Some of these technical difficulties were clearly explained by Paul Nicastri of Ford Motor Company’s Research Laboratory at the 2001 International Automotive Technician Network (iATN) Convention in Dearborn, Michigan.

Special arc-suppressing connectors, he stated, would have to be developed, and, most likely, the system will necessarily need to be shut off before servicing, using the types of switches found on existing hybrid vehicles.

June 2009 | MasterTechnician Online

W h at Happened to the 4 2 V S y s t e m ? Nicastri also demonstrated the increased corrosion factor of wires under a 36-volt load, compared to 12-volts. Enclosed, protected connections, he said, will have to be devised.

18 Cells! Batteries pose a number of problems. High voltage batteries will need to be durably encased for protection in case of collision. The connectors will have to be designed to cut the threat of arcing. Special dual-stage relaycontrolled connections that shut off power while the main contacts wed, then reconnect have been proposed. Delphi developed a prototype a few years ago, but it was never produced for the mass market. The need to jump or charge 36 volt batteries is another concern. Special connections and devices will need to be designed. The ability of a 36 volt lead acid battery to safely withstand even momentary reversal of polarity has not been established. Mistakes can happen, even with professionals. Just imagine the possibilities with a non-savvy vehicle owner.

70 MasterTechnician Online | www.mastertechmag.com

The SAE began to address these obstacles in the late â&#x20AC;&#x2DC;90s by setting up standards committees. The Electrical Distribution Systems Standards Committee authored a standard known as J2622 - Battery Connections. Its purpose was to â&#x20AC;&#x153;define test methods and set standards for development, production, and field analysis of electrical terminals, connectors, and components that constitute the direct connection to the storage battery of road vehicles having 42 volt nominal electrical systems.â&#x20AC;? At last check, the committee had developed a model for a safe battery connection, but has not met in some time. Another obstacle is the adaptation of lighting systems to the proposed 36/42 volt architecture. Preliminary testing indicated many problems with interior lighting, which would need to be stepped down to a lower voltage. Exterior lighting, especially headlamps, require further research to find cheap and efficient ways to utilize 36/42-volt energy. Without some basic redesign, headlamp filaments would have to be much longer and thinner, resulting in increased fragility and shorter burn life.

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W h at Happened to the 4 2 V S y s t e m ? One possible answer is adapting the technology known as Pulse Width Modulation (PWM). Used in other areas for years (remember feedback carbs?), PWM is simply a switching on and off of the voltage, resulting in a square wave form. With the duty cycle cut in half, many of the problems associated with arcing and corrosion could be addressed. Much research and engineering would, however, be needed to develop PWM devices suited to automobiles. The SAE launched a program to investigate the use of PWM in late 1999. The SAE 42V Exterior and Interior Lighting Cooperative Research Program brought together automakers and electrical suppliers to discuss PWM adaptation, testing and use on incandescent lamps. These lighting problems are another reason to advocate dual 12/14 and 36/42-volt systems within a vehicle. Even the top automotive business analysts were way off in their predictions, prognostications and projections. At the beginning of the decade, Standard & Poor’s estimated 72 MasterTechnician Online | www.mastertechmag.com

that car makers would build 46,000 vehicles with 36/36/42-volt electrical systems in 2002. This number was expected by S&P to increase to nearly 13 million by 2010. It isn’t going to happen – at least not anywhere near that quickly.

What’s Out There Now There are vehicles operating with 36/42-volt systems on the road today. General Motors began building and selling light hybrid models of its full sized Chevrolet Silverado and GMC Sierra pickups with dual 36/42-volt and 12/14-volt systems in 2004. The sales numbers have been miniscule and GM has used these trucks as a sort of test fleet. GM eliminated the conventional starter and generator in favor of a compact integrated starter/ alternator (ISA) located in the transmission bell housing. This flywheel/ISA/torque converter creates up to 14,000 watts of continuous power, which is stored

in a lead-acid battery pack for use in starting the vehicle, powering the electro-hydraulic power steering system and providing 120-volt AC power for plug-in outlets â&#x20AC;&#x201C; two in the cab and two near the rear of the load bed.

A control module regulates the flow of energy into and out of the starter generator. It also converts the current into different types for different purposes: 42 volt DC is converted to AC for starting, braking-regenerated AC is converted to 42 volt DC for recharging the glass mat battery

The integrated starter alternator (ISA) includes a rotor and stator, housed inside the transmission bell housing. It receives current from the storage battery pack to start the engine, then converts to a generator to create current, which is sent to the battery pack (courtesy GM).

June 2009 | MasterTechnician Online

W h at Happened to the 4 2 V S y s t e m ? pack, 14-volt power is converted to 42 volt for jump-starting, 42 volt is converted to 14 volt for the alternator function, and 42 volt DC is converted to 120 volts AC for powering the electrical outlets. Does this system sound complicated enough for you? Regardless, this complex technology makes the two GM pickups ideal for construction, agricultural and industrial uses.

As of last October, Ford, MIT and others were still working on â&#x20AC;&#x153;The acceleration of the development of new 42-volt high-voltage vehicle electrical system standards through the use of virtual engineering concepts and global consensus.â&#x20AC;? Delphi and many other deeply-involved supplier companies have put 42-volt research on the back burner, or are no longer pursuing it at all.

The control module, shown here in the corner of the engine compartment, regulates the types and levels of electrical current used in the GM light hybrid system (courtesy GM).

74 MasterTechnician Online | www.mastertechmag.com

As It Stands Many requests for interviews and information on the status of 36/42volt initiatives to tier one suppliers, automakers and involved associations in the preparation of this article went unanswered or were tersely dismissed. This leads one to believe that the whole idea of converting to 36/42-volt architecture may have been mistakenly undertaken. That nobody in these organizations wishes to openly discuss their conversion efforts speaks loudly. Perhaps it was premature. or the perceived need caused a competitive panic that resulted in depletion of monetary and human resources. Maybe the rapid advances in ultrahigh voltage hybrid technology have leap-frogged the need for 36/42-volt systems. It is to be hoped that the annual global gathering of automotive engineers at the SAE World Congress in Detroit this month will shed new light on the future of these systems. We’ll let you know. The integration of 36/42-volts – if it ever comes – will impact the entire

industry from top to bottom, from beginning to end, involving vehicle manufacturers, tier one suppliers, parts makers and service suppliers, tool and equipment sources and the aftermarket and independent service facilities. It will be the most costly, most time-consuming and most radical event ever to happen in the automotive industry. It would make the switch to automatic transmission, electronic ignition, or disc brakes seem like a walk in the park. The 12/14-volt architecture we’ve used since the mid-‘50s continues to evolve and still serves us well enough. But, it does have limitations. Just as 6-volt systems needed to be raised after almost half a century, perhaps it’s time to move forward again, fifty years later. The onus rests on those who have the most to gain from the change – the automakers. Once they find it necessary, feasible and cost-effective to make the change to 36/42 volts, we in the aftermarket will have to follow with training and lots of new tools and equipment if we want to keep pace with the rapidlymarching parade of technology.

June 2009 | MasterTechnician Online

Another Mystery Solved:

Hocus Focus The

little

Ford

that

couldn’t

by John Anello

shop called me in to investigate a 2002 Ford Focus with 2.0L that had poor power on a hard acceleration (Figure 1). The vehicle, which only had about 53,000 miles on it, idled fine with no misfires or codes stored in memory. It just didn’t have the horsepower it should have had. The shop had already replaced the fuel filter and performed a backpressure check to rule out a clogged catalytic convertor. The owner was told by the garage that there was a possibility that the fuel pump was bad and it was suggested that he go to the new car dealership to have it changed under warranty. When the Ford dealer’s tech checked the car, 76 MasterTechnician Online | www.mastertechmag.com

he had a different opinion of what was needed to fix the complaint. He recommended a new transmission because of the lack of torque and a concurrent condition of engine flare-up on acceleration. The torque multiplication at the wheels just did not seem to be adequate. At this point, the customer called the garage owner to let him know about the outcome at the dealership, and the garage owner recommended a local transmission shop for a second opinion. The trans shop proved the dealer wrong, and now the vehicle was back at the garage for further investigation. This poor car was like a carnival ride -- everybody wanted to take a turn in the driver seat. There were too many opinions and no solid answers.

When I arrived at the shop, I drove the vehicle to get a feel for the problem the others had experienced. I warmed the car up and it seemed to rev fine with no hesitation problems. The engine idled smoothly with no misfires or apparent roughness. I placed the transmission in drive and accelerated normally from a dead stop, and it did not seem bad at all. Then, I tried hard acceleration. It seemed to accelerate fine without holding back, but it took

too long to come out of first gear due to the amount of throttle needed to get the vehicle going. Holding the throttle down farther created an engine flare-up, which was followed by a bang into second gear. It felt like a bad transmission, but then again it seemed like the engine did not have the top-end torque it was designed to have. At this point, I needed to run some tests to determine if the

Figure 1 June 2009 | MasterTechnician Online

H o cus Focus engine was experiencing a fuel, air/ exhaust flow, or timing problem. I started my diagnosis by checking for codes in memory, and there were none present (Figure 2). The EVAP monitor had not run yet, indicating that someone had erased prior codes and stored freeze frame information, but the vehicle did run all the other monitors proving out any fuel trim or misfire conditions. When dealing with a low-power condition, it is important to know that most of the failures I have seen in the

Figure 2 78 MasterTechnician Online | www.mastertechmag.com

field fall into the common categories of lack of fuel, restricted air intake, clogged exhaust, miscalculation of volumetric efficiency, or an ignition/ valve timing issue. It was easy to just watch data parameters on acceleration to determine if the problem was fuelrelated, so I accelerated the engine again from a dead stop at wide open throttle while viewing some selected PIDs (Figure 3). You can quickly see that the PCM maintained fuel control during the whole time indicating that the power loss was not due to a fuel problem. Had it been a lack of fuel, I

would have seen fuel trims maxed out with an O2 sensor value constantly below 500mV. Providing that the O2 is working properly, this quick test eliminates the need to get too intrusive by hooking up a fuel analyzer to check fuel pressure and volume. Now that I had eliminated the possibility of a fuel delivery problem, my next step was to perform a volumetric efficiency test to check air flow through the engine. After all, the engine is nothing more than an air pump and the PCM will use

the MAF calculation to determine the proper fuel and ignition timing mapping to keep the engine at peak performance. The correct air flow reading is dependant on the proper calibration of the MAF, the amount of restriction in the air inlet and exhaust system, and valve train integrity. To be accurate, this test has to be done at wide open throttle while driving. You also need to take into consideration the ambient air temp, altitude and engine size. This can be done by recording your captured scan data into a VE calculator, or by

Figure 3 June 2009 | MasterTechnician Online

H o cus Focus simply plugging your engine and ambient conditions into the Escan VE program and letting it do all the work for you while you concentrate on your driving skills to maintain a steady wide open throttle acceleration to capture the data you need. Once the proper information was entered into the VE program, I put the pedal to the metal from a dead stop and captured the air flow data (Figure 4). The actual volume of air was 30% below the calculated specification. There were no fuel

Figure 4 80 MasterTechnician Online | www.mastertechmag.com

trim issues, which indicated that the MAF was correct in its findings. The exhaust back pressure had already been checked by the garage and found to be below three psi, and the air inlet and air filter were checked for restrictions and were okay. This problem was valve train related. I next hooked up my scope and tagged the crank and cam sensors to perform a correlation check by viewing the signals in a superimposed format (Figure 5) to prove my suspicions. By pulling up a known-

H o cus Focus good pattern from my Ace Misfire database (Figure 6), I could see that the crank and cam correlation was off by about 60 degrees. This is a quick and easy check to validate mechanical timing issues with trigger points, but it alone still cannot prove out a jumped timing chain or belt. There have been too many situations where I have found loose trigger wheels that had lost their indexing, damaged flywheels, worn crank pulley keyways, or even sheared cam gear pins. The only true way for me to quickly prove out a valve train problem would be to

Figure 5 82 MasterTechnician Online | www.mastertechmag.com

use a 300 psi pressure transducer in a cylinder to get a true indication of piston and valve correlation. I removed the spark plug and placed a spark tester on the wire. I next screwed the pressure transducer and adapter assembly into the cylinder and started the engine to capture a waveform. I shut down the engine and zoomed in on the pressure pattern to view the peak-to-peak pressure rises indicating one combustion event of 720 degrees. I placed the cursors on the peak-to-peak compression rises and then hit the Cam Timing

button within the EScope program (Figure 7). The program automatically placed five large purple cursors creating four divisions of 180 degree of crankshaft rotation and five smaller purple cursors creating six subdivisions of 30 degrees on the screen. You could now see that the exhaust valve was opening at about 75 degrees before BDC of the power stroke (note that the lowest fall after the compression rise is where the exhaust valve begins to open). Having seen many waveforms showing exhaust valve openings between 3045 degrees before BDC of the power

stroke, this engineâ&#x20AC;&#x2122;s valve timing was definitely off by 30 degrees or better. It was now safe to instruct the garage to pull apart the front timing cover, which involved supporting the engine with a jack, removing an upper engine support and removing an upper metal timing housing cover -- all that just to expose the timing belt. Once the timing belt cover was removed, I marked the sprockets with White Out (Figure 8). The cam gear was off by about two teeth. Also, the belt had some slop indicating that

Figure 6 June 2009 | MasterTechnician Online

H o cus Focus the self-adjuster was not doing its job of compensating for belt stretch. The fix here was to sell the customer a timing belt and a new belt tensionor. I also recommended replacing the water pump that ran off the belt as a preventative maintenance measure. Prior to being a mobile technician for the last 15 years, I worked in an engine rebuilding shop for five years and as a dealer technician for another 10 years, and I have seen so many guys in the field skimp on so many types of jobs to try to save a customer money by not replacing a component that may

Figure 7 84 MasterTechnician Online | www.mastertechmag.com

involve overlapping labor time. An experienced tech should understand that educating a customer is the best way to sell needed work on a vehicle. Doing this good deed will help to prevent a return visit of the vehicle on the hook. I find that whenever you try to save a customer money you always lose in the end. Itâ&#x20AC;&#x2122;s amazing to me how this Focus timing belt went undetected by the PCM, or even by a dealer tech who knew Ford products well. On the other hand, I can see this happening to any

H o cus Focus

tech because there were no obvious signs that you would normally associate with a jumped timing belt, such as poor engine vacuum, rough idle, engine misfire, dramatic loss of power, erratic electronic spark operation, or even popping through

the intake. This was a tricky Hocus Focus that deceived everyone into thinking that anything could be at fault except the timing belt. Even when I drove the car, I thought the engine was all right and I was leaning toward performing a transmission stall speed test because it did seem like a transmission problem. I believe that the key to resolving power issues is to keep it simple by performing pinpoint tests to validate engine performance, which can have an effect on transmission performance. Using â&#x20AC;&#x153;feels likeâ&#x20AC;? or failure pattern tactics will only lead you down a dead end street where you wonâ&#x20AC;&#x2122;t find the resolution to the initial problem. I always strive to find new ways to finetune my diagnostics to cut down on labor-intensive intrusive tests and component removal. As the technology in equipment advances, it can only help us to achieve new levels of diagnostic strategies. I hope this story helps you choose the right path when you hit that diagnostic fork in the road.

Figure 8

86 MasterTechnician Online | www.mastertechmag.com

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A/C Leak Sealer: A Controversial Last-Resort Fix by John Hess

Bone of contention: Will A/C sealant save the day or destroy Western Civilization? (courtesty Cliplight)

ypically, this is considered suitable only for older cars that aren’t valuable enough to warrant the cost of an expensive evaporator replacement. Our old friend John, however, gives us the rest of the story. It’s that time of the year again. My e-mail inbox is stuffed with pleas for help in finding that magic retriever of cold air -- a low-cost refrigerant system sealer. It’s either that, or 88 MasterTechnician Online | www.mastertechmag.com

they’re asking whether or not to use one in the first place. While sent in by folks of every stripe, these requesters all seem have two things in common: They’re cooking in their vehicles and desperate for relief, and their A/C systems won’t hold a charge. Well, maybe they have a third thing in common: They can’t or won’t pay to have a professional A/C shop fix the system properly.

The normal reasons given for not having the shop fix it are: 1. They don’t have the money. 2. The vehicle isn’t worth the cost of a righteous repair. 3. They only need it for one more season. Or, all three (Number 2 is especially applicable in states like California where older vehicles may not pass their next smog check). Here are examples of the messages I get. While some are definite candidates for a sealant, others obviously aren’t: ”My buddy is thinking about putting some air conditioner stop leak on his ‘95 Grand Am. I have never heard of this before and my first impression is don’t do it. I’ve always heard not to get anything in the air conditioning system. Has anybody tried this stuff before? The compressor itself

is leaking (has a crack) and he thinks this might get him thru the summer. Will this damage the system in anyway? Thanx in advance!” Forget it -- a cracked compressor and he’s worried about something damaging the system?

Here’s another: “I own a 1995 Plymouth Voyager and I have been told that I have a small leak in my evaporator. What I would like to know is if there is a way to fix this without having to take the dash off of my car. The air conditioner is located behind the dash. I have been given an estimate of $500.00 to replace the evaporator. I am basically looking for some information that would tell me if there is something my husband could do to fix it ourselves. Any help you could give me would be greatly appreciated. Thank you, Jane”

June 2009 | MasterTechnician Online

A / C Leak Sealer Wow, talk about a tough sale. Though that price is couple of years old, it was still quiet reasonable at the time. Most evaporator replacement jobs then were at least $1,000. But Jane still wouldn’t go for it. As Tony Soprano would say, “Whatareyougonnadoaboutit?” Since most Chrysler and Jeep evaporators are good candidates for sealing, how about someone offering to take a shot at fixing it with a professional leak sealer? You can find more testimonials, both pro and con at: http://www.imcool.com/articles/ aircondition/ac_sealants_p2.htm

Up front, I’m well aware of the negative feelings (to say it nicely) that most A/C shop owners and techs have about sealers. I also hear from the other side, however, brethren of the above who are using sealers quite successfully. Joe Fortunato (Automotive Air & Specialty, Jupiter, FL), for instance, a 39-year A/C tech and 25-year shop owner, is not shy about using the Cryo-Chem product. He’s been installing it for several years and gets a 98% success rate when used on true candidate vehicles, such as the Plymouth Voyager above. Joe doesn’t offer a warranty on the service, but if the sealing job doesn’t hold, he will credit the cost toward a full evaporator replacement service.

How A/C sealants entered the vehicle market

We got this shot of a clogged orifice tube from the field. A do-it-yourselfer didn’t follow the proper procedures and really loaded the system up with sealer. 90 MasterTechnician Online | www.mastertechmag.com

As additional support for the viability of Cryo-Chem and sealants in general, I offer snippets from a post to the bulletin board at www.aircondition.com by George H. Goble, better known a few years on the internet as “ghg.”

Background: George is the inventor of several R-12 alternative refrigerants, one of which is GHG-X3 that he introduced in 1990. Later classified by ASHRAE, it became known as R-406A, and eventually by the trade name “Autofrost.” Yes, it is a “blend” refrigerant (more on blends in a future MT article). Here’s how George described his first “fix” in 1982 of his 1978 Datsun 810’s leaking A/C system: “At first, I ran small tubing (1/8” copper), and put a manifold and dry-eye in the passenger compartment. And drove around with a 30lb cylinder of R12 in the back seat…and when the system got low, just opened up the low side manifold valve and put in another pound of 12 while I was driving! Hell, a 30lb cyl of R12 was only $30 back then and lasted all summer! What ozone hole? When fully charged, and hot, it lost about 1 pound/week.”

George was ready for a leak sealer, and lo and behold: “I met up with JJ Packo around that time. My home central A/C (R22) had started leaking about 1-2 lb/month (4 years old)… They had a SSR12 “kit”, that was two cans of R12, one with some “dry-pak” dissolved in the R12, and the 2nd with some cryosilane (gaseous epoxy) dissolved in the R12. Kit was about $100.”

Take one “Home” A/C system leak sealer kit, try it in a leaky car, and voila! “Instructions were to put on a new dryer, and change the orifice tube (this car had an expansion valve). I didn’t change the dryer, but did a 10 min. vacuum, charged in the 1 lb can of drypak (about 2% dry-pack concentrate, rest is R12), put in a can of R12 (now at 2/3 charge)... and ran car for 1/2 hour to circulate the dry-pak, which converts the free moisture into silicone

June 2009 | MasterTechnician Online

A / C Leak Sealer oil (so it doesn’t form acids anymore, and in this case, removes the moisture, so the cryo-silane won’t activate). Next, added the Cryo-silane (about 3% cryo-silane concentrate in 12oz of R12), and now at full charge.

For a couple of days, I noticed the cryo-silane “dead fish” odor when starting up the A/C (evap leak). After two days, odor was gone, voila, it worked. It self-sealed the evap leak! And it held. That car never leaked again. And in 1990 it became the “development” car for GHG refrigerants: GHG-X1, X2 (HCs), GHG-X3 (R-406A/Autofrost), and GHG-HP. In 1993, the fuel pump died (but the A/C still worked), so I junked the car.” Interested readers are encouraged to read ghg’s entire post at: http://www.aircondition.com/ wwwboard/current/18951.html

92 MasterTechnician Online | www.mastertechmag.com

For those needing more evidence of George’s refrigeration bona fides, he is a senior systems engineer for the Engineering Computer Network department at Purdue University. Besides inventing, patenting and developing several substitutes for Freon, check out the paper he and colleagues presented at the Purdue 1992 International Refrigeration Conference -- Energy Efficiency and New Refrigerants: http://www.autofrost.com/peoples/ ghg/ghg-ternary.pdf. For those of you techs who believe you know everything there is to know about R-12, R-134a, and associated lubricants, I challenge you to read this piece and not learn something new. If you’re still convinced that sealants aren’t a viable service for “legitimate” A/C shops, I ask you, would a man who understands more about refrigerant systems— including vehicular—than most of us could absorb in a lifetime, flippantly suggest the usage of something that would damage them? Not hardly.

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A / C Leak Sealer

Do-it-yourselfers are the problem So far, the sealant manufacturers and parts houses have probably been cheering this piece. Here, however, is where we will probably part company (I might even regain some shop owner/technician supporters). While it’s not illegal (where are the environmentalists?), it certainly is somewhat unethical, in my humble opinion, to offer these products to the DIY public. Why? For one thing, because of the age-old human adage that if one shot didn’t do it, give it another [Editor’s note: How abour, Too much is not enough?]. That’s how systems truly do get fouled. Then, if you need a certificate to buy refrigerant and work on refrigeration

systems, why don’t you need a certificate to buy refrigerant-sealing products that circulate within the refrigerant? I’ve not (yet) asked the manufacturers, nor reps from the EPA, that question, but someone really should. Cliplight, a manufacturer of two A/C sealants, Super Seal HVACR 944Kit and the Super Seal Premium 946Kit, has commented publicly on what DIY sales of sealant products can bring: “It should be appreciated that the marketplace is full of A/C leak sealers that are sold directly to the DIY segment and these products are injected into an A/C system without any measure of pre-inspection of the system or control during the injection process. It’s also worth noting that these products often contain: · Hydrocarbon propellants that will contaminate a reclaim bottle.

For some people, too much is not enough. 94 MasterTechnician Online | www.mastertechmag.com

· D yes visible to the naked eye without the use of a UV light source that, under certain

conditions, can develop crystalline formations in the system and neutralize the fluorescent dye intensity.”

Should the a/c system fail to respond successfully to this DIY treatment, the consumer -- in final desperation -contacts a qualified service technician. Most professional techs will refuse to work on a vehicle that has had DIY “cocktails” injected into the system. If he does the first stage evacuation process, it could present him with nasty surprises! Especially if the system had been contaminated with moisture saturation (undetectable by the DIY consumer).

Protecting the compressor Understandably, most vehicle manufacturers, along with A/C component and recovery equipment makers, are not proponents of A/C sealers. As a rule of thumb, if they find remnants of a sealer in anything returned for warranty, the claim will

be denied. When a shop uses a sealer in a system, either the shop or the vehicle owner assumes responsibility if contamination causes a problem. Most technicians who use the product will advise the customer that it is a last ditch effort; there is no warranty. Note: Cryo-Chem, SSR International does offer dealers a limited one-year warranty with its SSR134Kit. It covers corrosion leaks in condensers and evaporators. The dealer must be 608/609 certified, follow SSR’s installation directions and satisfy other requirements. Cliplight Manufacturing not only offers a limited one-year warranty on its product, but also, under “Coverage B,” covers many A/C components. For instance, if SUPER SEAL PREMIUM was found (by Cliplight) to have caused the failure of the compressor, Cliplight will reimburse the dealer up to $350. Since several conditions and exclusions apply, be sure to check the web page for the details: http://cliplight.com/automotive/ products.php?pageID=Warranty& productID=16&catID=4

June 2009 | MasterTechnician Online

A / C Leak Sealer

Contamination protective devices

(Above) This recycling machine solenoid is plugged with A/C system sealant. Not good.

Recycle Guard from AirSept: To protect your refrigerant recovery equipment and clean jugs of refrigerant, you do not want to recover sealer-laden or otherwise contaminated refrigerant. Airsept’s Recycle Guard uses high-tech filtration to separate and remove sealant, dye, lubricant and solid contaminants from the refrigerant. These remain in the canister while the vapor refrigerant exits to your A/C machine (www.airsept.com/). System Guard from SYSTEMGUARD: To show if someone has tampered with your A/C service job (such as a vehicle owner adding contaminated refrigerant or DIY “stop leak,” then blaming you for the disastrous results), slip either a heat-shrinkable System Guard sleeve or plastic tie wrap over each service port. They’re color coded and serial numbered. Once heat shrunk or crimped to the port, any disturbance will be clearly visible (http://www.acsystemguard.com/).

(Left) Here’s the best way we know of to keep sealer and other contaminants out of your A/C machine (courtesy AirSept). 96 MasterTechnician Online | www.mastertechmag.com

Whether you strap them on as shown, or heat-shrink the sleeve type, tamper-evident service port protectors will let you know if somebody’s been in there since you last worked on the vehicle (courtesy Systemguard).

Neutronics QuickDetect A/C Sealant Detection Kit: QuickDetect is designed to act as an A/C leak. If sealant is present in the system, it quickly solidifies in the disposable test cartridge causing the flow meter to show “no flow.” When attached to the high-side port, if the flow

meter shows constant flow for two to three minutes, it’s most likely sealant free. If the flow rate visibly decreases, the refrigerant contains a sealant. Other than the low-cost test cartridges, all of the QuickDetect components are reusable (http://www.refrigerantid.com/).

June 2009 | MasterTechnician Online

A / C Leak Sealer

This cleverlyconceived kit tells you whether or not there’s any sealant in the system so you can decide how to proceed (courtesy Neutronics).

John Hess, a Viet Nam vet, entered the radiator repair business in 1971. He is the editor and publisher of Cool Profit$ magazine (www.imcool.com), a professional journal targeted to radiator and A/C technicians and shop owners, and the Heat Transfer Service Network (www.goHTSN.com).

98 MasterTechnician Online | www.mastertechmag.com

For more information about sealants, check out the air conditioning pages of www.imcool.com. Not only will we offer a “Blog,” but also your “Comments” can be added to our articles that contain controversial subject matter.

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The results were clear: these hubs were not OE quality hubs. They were “value” grade hubs, which are no real value. Not only do they fail quickly, they can result in excessive NVH (noise, vibration and harshness), braking and handling problems, and expose drivers to potential safety risks. Don’t compromise your customer’s vehicle safety. Always install SKF premium quality hubs! See the results of our test at www.vsm.skf.com

You donâ&#x20AC;&#x2122;t need that old black magic to fix runflat tires.

The idea of reinforced sidewalls seems simple enough, but what does it do to the ride, and how are you going to demount/mount such rigid tires (courtesy BMW).

100 MasterTechnician Online | www.mastertechmag.com

by Dave Russ

aaaaaaaahhhh, runflat tires . . . No more jack, no more spare. No more air, no more repair. And you can ride on ‘em forever, right? Not quite. Most self-supportingtype runflat tires -- for example, Goodyear and Dunlop Extended Mobility Tires (EMTs) -- are essentially tires with ultra-stiff sidewalls that don’t flex very much when there’s little or no air pressure, and thus can be run “flat.” (DISCLAIMER TO TIRE ENGINEERS: There’s a ton of extremely sophisticated material and construction engineering involved, okay?) Runflat tires can be driven at up to 50 miles per hour for 150 miles or so (your mileage may vary; see owner’s manual for details. . . .). The idea is to get you to a repair facility in case of a flat.

Assuming you don’t exceed the limits above and don’t shred the tire, they can be repaired. CAUTION: Some car manufacturers, BMW for example, don’t recommend repairing runflat tires, which makes for some interesting conversation on BMW owner blogs.

Beemer bloggers blast away For example, “Louis,” Member #2567, wrote in January that he was considering leasing “a 2007 328i sedan, which (like most or all new BMWs) comes with runflat tires. Like most people, I don’t like the idea of runflat tires. I just can’t stop thinking about the problems I will have to deal with if one of the tires goes flat. What I have heard is that one can drive 50 miles or so on the flat.”

June 2009 | MasterTechnician Online

101

Yo u Can Repair Runflat Ti r e s

To which “Doug” replied, “You are not alone and as of right now the whole run-flat tire scam should be worrying everyone that enjoys high performance automobiles. But I will refrain from a full ranting and hopefully we will see some better answers along with some unbiased commentary in the BMW CCA Roundel magazine soon. HINT! HINT! “To answer your questions the range is 150 miles driven gingerly. No, they should not be and most of the independent tire dealers I have spoken with will not repair them. Yes, by all means they can be replaced with

102 MasterTechnician Online | www.mastertechmag.com

Demounting/mounting tires with such stiff sidewalls isn’t easy, but our friends at Hunter Engineering supplied this series of photos to show us how to do it without damaging the bead. First, get as much lube on the upper bead seat as possible so the bead can slide down into the drop center of the rim without too much force being applied.

non-runflats on the same wheels. Yes, they are expensive to replace if they go bad and, no, your local tire dealer is not likley (sic) to have them in stock, although your BMW dealer may, at tire prices only the devil himself would charge. I have heard rumors of $600+ each.

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Yo u Can Repair Runflat Ti r e s

(Above) With one side deeply into the drop center, you should be able to lever the opposite side over the lip of the rim.

104 MasterTechnician Online | www.mastertechmag.com

(Below) For mounting, you start this bead depressor â&#x20AC;&#x153;tailâ&#x20AC;? . . .

. . . then insert these spacer blocks to keep the bead down in the drop center. If you tried to just force it, you’d tear the bead and perhaps damage your nice tire machine.

And another thing: “They ride horribly” The blog continues: “That doesn’t end the problems of runflats, either. They also ride horribly on every new BMW I have driven them on. If I had a new BMW coming my

way soon I would bite the bullet and either make the dealer install comparable non run-flats as part of the overall purchase or lease price... Or buy them myself and install them as soon as possible. “The whole idea of the runflats is to aid in eliminating the spare tire for packaging purposes, etc. That is perfectly fine with me as I think they should be eliminated also. But roadside assistance and a June 2009 | MasterTechnician Online

105

Yo u Can Repair Runflat Ti r e s

The Michelin PAX system is another concept entirely. That inner ring supports the car, not stiff sidewalls, so ride quality isn’t affected. We wonder how you demount/mount without the extra space normally provided by an open drop center.

decent inflator kit is a much better solution than runflat tires unless they improve drastically.” Now that he mentioned it, tire makers far and wide recommend against using aerosol inflators to fix flats. Why? While they may seal the leak, if it was caused by a penetrating

106 MasterTechnician Online | www.mastertechmag.com

object, that object is likely to still be in the tire and must be removed. Additionally, if the tire is up and running, a false sense of security and forgetfulness could lead to nonrepair of the tire. Third, the goo from the inflator makes quite a mess – not much appreciated by the person who ultimately repairs the tire.

d e b a

sidebar i d e b a r GOODYEAR PRODUCT SERVICE BULLETIN

Unlike some other manufacturers, Goodyear says its runflats can be repaired providing the proper procedures are used.

Here are the Goodyear runflat repair instructions verbatim, which are applicable to other runflat tires, too; however, not all runflat manufacturers recommend repair and say you’ll void the warranty if you do it.

S U B J E C T: Puncture Repairing and Retreading of tires that are “H” INCORRECT OR IMPROPER Speed-Rated and higher (equal to REPAIR WILL RESULT IN THE or greater than 130 mph) includes TIRE NO LONGER BEING SPEEDGoodyear EMT & Dunlop DSST tires. RATED BY GOODYEAR and the warranty may also be affected. A Goodyear, Dunlop or KellySpringfield manufactured speedR E A D I N G : If a Goodyear, rated tire may be repaired to correct Dunlop or Kelly-Springfield a commonly repairable nail hole manufactured speed-rated tire is puncture in the tread area only, but retreaded, it no longer is speed rated proper materials and procedures by the company (and most runflat must be applied. tires are, by and large, speed-rated).

Yo u Can Repair Runflat Ti r e s

The French way

Goodyear’s attitude

There is another type of runflat tire, the Michelin PAX System, consisting of a conventional tire and an inner composite-type ring mated to the wheel. When the tire goes down, the weight is supported by the ring. As for repair, Michelin advises that the tire should be taken to an authorized Michelin PAX System repair outlet. Michelin has set up service centers around the United States, including all Honda dealers. A toll-free number finds the nearest one. Part of the PAX warranty is to replace any PAX wheeltire system that has incurred air loss.

“Some tire makers disallow puncture repairs on runflat tires,” says Goodyear spokesman Jim Davis. “However, punctures in our runflat tires can be repaired, according to the same guidelines as other tires. The servicing outlet needs to obtain information from the driver, and inspect the tire to make certain there are no signs of the tire being degraded due to being run at zero pressure for an extended period, much the same as an outlet would treat any other punctured tire. In any case, there is a product service bulletin on the proper repair of speed-rated tires, which includes EMTs” (see the sidebar).

Goodyear says, “Like any other Goodyear speed-rated high performance tires, the Goodyear runflat EMT tire may be repaired to correct a nail hole puncture in the tread, but proper materials and procedures must be used.” Goodyear supplies runflats for a number of OEM vehicles, including Corvette, Mini Cooper, Cadillac CTS-V, Rolls Royce, Lexus SC430, Maserati Quattroporte, Ferrari F360, Jeep Grand Cherokee SRT8 and several BMW and Mercedes models.

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If you want to bag it and send the customer to a Goodyear RunFlat EMT service facility, or to get information on proper repairs, call 1-800-RUN-FLAT. For other tires, be sure the repair doesn’t void the warranty, although even if it does, the customer may want you to go ahead and repair the tire so he or she can get back on the road.

DETAILED POLICY Puncture Repair of Speed-Rated Tires A. The puncture must be confined to the tread area only. B. Restrictions on the number and size of repairs must be followed. C. A detailed repair procedure must be followed. D. A speed-rated tire repaired in strict accordance with items II-A, B & C will retain its speed rating.

REPAIR PROCEDURE FOR SPEED-RATED TIRES GENERAL The objective of the puncture repair is to seal the tire against loss of inflation pressure and to prevent damage to the carcass from moisture. In all puncture repairs, approved by Goodyear, Dunlop and KellySpringfield, the hole must be filled with a plug, and a patch covering the hole must be applied according to repair material manufacturer

instructions to the inside of the tire. Never repair tires which are worn below 2/32â&#x20AC;? tread depth. NOTE: NO TIRE IS TO BE REPAIRED WITHOUT FIRST BEING REMOVED FROM THE RIM. REPAIR AREA Repairing is limited to the tread area only within the outside grooves. No repairs are allowed in the tread area beyond the outside grooves or in the sidewall area of the tire.

D. MATERIALS NEEDED 1. Precured rubber plugs - 1/4â&#x20AC;? (6mm) diameter 2. Precured patches 3. Precured plug/patch combi-units 4. Chemical vulcanizing cement 5. Pre-buff cleaner E. REPAIR PROCEDURE 1. Carefully remove completely from the rim.

the

tire

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Yo u Can Repair Runflat Ti r e s 2. Locate the puncture on the inside of the tire and circle with crayon. 3. Remove puncturing object if it is still in the tire. 4. Carefully inspect tire on a good tire spreader, with ample light, that will show any cracks, breaks, punctures, damaged or broken beads. 5. Check liner for cuts, cracks, or holes which may cause the tubeless liner to lose air. 6. Check the injury with an inspection awl: a. D etermine size and angle of injury.

NOTE: If the hole shows evidence of fabric splitting, such an injury cannot be properly repaired using this puncture repair procedure. Such an injury must be skived out and repaired as a section (reinforced) repair, which will maintain the serviceability of the tire, but will invalidate the tire’s speed rating. If a section repair is necessary, the customer must be advised, before the repair is made, that the tire will lose its speed rating, and must not exceed operation at normal highway speeds. 9. Use a pre-buff cleaner and a scraper to remove contaminants from the liner in the area to be buffed around the injury.

b. Check for ply or belt separation.

10. Use a 7/32”carbide cutter for ¼” repairs to clean out the puncture.

7. Reject any tire that has separation, loose cords, damaged bead(s), or any other non-repairable injury.

a. Make sure that the drill follows the direction of the puncturing object.

8. If the hole is simple and round, steps 9 through 17 of the puncture repair procedure will be successful.

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b. Always drill from inside to outside of tire.

11. Using chemical vulcanizing cement, lightly coat at least 1/2 of tapered end of the repair plug. Install the plug in the prepared puncture according to the manufacturer’s instructions. Trim the liner side of the plug slightly higher than the surface of the liner without stretching the plug. 12. Center the patch (or patch template) over the injury without removing the backing. Adhere to patch or template instructions, as to positioning as related to bead location. Using a marking crayon, mark around the outside edge of the patch, approximately 1/4” larger than the patch. 13. Buff the liner and plug at the puncture location. The buffed area should be slightly larger than the patch. The buffed surface should be finely grained (RMA 1 or 2 texture) and even for proper bonding. Use care to prevent burning the rubber with the buffing tool. Do not buff through the liner. Do not buff into the marking crayon. Clean the buffing dust from the tire using only a vacuum or brush. Do

not use gasoline or other petroleum solvents on the buffed area. Coat the buffed liner surface and the patch with one evenly applied coat of chemical vulcanizing cement in accordance with the recommendations of the repair materials manufacturer. Allow the cement to dry thoroughly. Do not touch the cemented areas. Install the patch with the beads of the tire in the relaxed position. Position the patch over the puncture according to the markings on the patch. Stitch the entire patch starting from the center, keeping the strokes close together to avoid trapping air under the patch. 17. Cut off the protruding end of the plug about 1/8” above the tread surface. FINAL INSPECTION -- The repair must seal the inner liner and fill the injury. After remounting and inflating check the repair, both beads and valve with a soap solution to assure a complete seal.

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Another Mystery Solved:

by John Anello

The Auto Tech on Wheels tells us how he used high-tech means to justify trans removal to find the real cause of a no-start

shop called me in to investigate a no-start condition on a 1996 Dodge Caravan with a 3.3L engine (Figure 1). This shop only had a scan tool in its arsenal of diagnostic equipment. No scope, no graphing meter combined with a component tester, not even a repair information system. With no codes in memory, the techs resorted to the â&#x20AC;&#x153;feels likeâ&#x20AC;? tactic. They used their best instincts to replace parts associated with their visual inspections and old-school test procedures. 112 MasterTechnician Online | www.mastertechmag.com

Figure 1

Bad PCM, but why? The spark tester they were using only showed spark on one coil, so the list of parts replaced included the coil pack, crank sensor, cam sensor and a PCM. The old PCM was bad due to a damaged coil driver that was holding one coil primary constantly on. Iâ&#x20AC;&#x2122;ve seen this many times in the field caused by a bad coil assembly with a shorted coil primary winding. So, I

could justify their replacement of the coil assembly and the PCM, but the vehicle still wouldnâ&#x20AC;&#x2122;t start. This shop is not alone in the way it diagnoses cars. All too often I cater to this type of shop, and I try my best to educate on-site how important it is for the technicians to keep themselves up to date on training and to have the proper equipment available for performing the tasks that will save them time and avoid replacing perfectly good parts.

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W h eel of Fortune This will obviously make them better technicians in the long run. Itâ&#x20AC;&#x2122;s never too late to step up and take it to the next level. The worst thing in any business is to let technology surpass you. You will only find yourself stuck in the past with not much of a future ahead of you. When I arrived at the shop I attempted to start the car, but it only spit back a few times as if it wanted to start. The tech told me that #2/5 ignition coil was

Figure 3 114 MasterTechnician Online | www.mastertechmag.com

the only one firing during cranking. The other coils did not fire at all. At this point I decided to hook my scope up to some selected signal lines to get a visual concept of what was going on exactly. I used my EScope Limited 4-trace scope and placed my channels on the cam sensor and all three coil drivers. As I cranked the engine, I could see that the cam sensor was providing the proper signal pattern, but the PCM had a problem controlling the coil drivers (Figure 2). One driver attempted to

ground the coil while another driver was held on for as long as 600mS of on-time. By current ramping the one working coil against the crank and cam signals (Figure 3) I could see that the coil driver was maintaining about 8.5 amps of current for almost one camshaft revolution. There is no way any driver would hold a coil primary that long unless that driver was in love and just did not want to let the coil go. It was a relationship that went bad, and no one was around to give advice

to just let go. That got me wondering if this might have caused the failure of the coil driver in the old PCM.

Out of synch This erratic coil operation could only be caused by a defective PCM with an internal driver failure, a corrupted crank/cam signal input, or a crank/cam sensor correlation problem. The cam and crank sensors

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W h eel of Fortune seemed to be producing the proper patterns with correct amplitude, but I needed to compare their synch correlation. I used my Ace Misfire crank/cam waveform database and pulled up a known-good crank/cam pattern for this vehicle (Figure 4). You can see how the cam sensor pattern repeats the 1-2-3-1-2 pattern while the crank signal repeats the 4-4-4-4-44 pattern. It is between where the cam pattern ends and begins that there should be equidistant 4-4 patterns. I

Figure 5 116 MasterTechnician Online | www.mastertechmag.com

imported the cam sensor signal into the measuring section of the scope (Figure 5) and placed cursors to show one complete event of the cam sensor. By hitting the Mark Camshaft button, the program automatically placed five purple cursors on the screen creating four divisions each representing 180 degrees of crankshaft rotation and five smaller purple cursors creating six subdivisions each representing 30 degrees within each 180 division.

W h eel of Fortune I superimposed the crank signal on top of the cam signal and zoomed in on the end and the beginning event of the cam signal (Figure 6). Notice how the crank signal has shifted at least 30 degrees to the left. This indicated that the crank and cam sensors were not properly synched. The cam sensor indexed off the front of the engine while the crank sensor indexed off the torque convertor at the rear of the engine. Now, I had to decide whether this

Figure 6 118 MasterTechnician Online | www.mastertechmag.com

was caused by a problem in the front or rear of the engine. With 108,000 miles on the clock it was a better sell from a maintenance point of view to disassemble the front of the engine to inspect the timing chain components than it was to pull the transmission to check the flywheel assembly. The cause at this point could be a jumped timing chain, sheared crank keyway, sheared cam gear roll pin, or even a damaged flywheel. There was no flywheel noise while cranking the

engine, so where do you start with this dilemma without having to spend unnecessary labor?

Cylinder pressure The answer to this question is a new test procedure Iâ&#x20AC;&#x2122;ve been using to check valve train problems that uses a simple 300 psi pressure transducer. You remove the spark plug from a selected cylinder and install a hose adapter to

accommodate the pressure transducer. Next, you place a spark tester on the plug wire of that same cylinder, put an inductive clamp around the plug wire and crank the engine. The resulting patterns will show you a peak-to-peak cylinder pressure rise representing a 720 degree crankshaft event and an induction square wave representing the spark event in the cylinder. You then place your cursors on the compression peaks, select the Mark Camshaft button and look at where the purple cursors

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W h eel of Fortune are laid out. The lowest point (u-curve) before BDC of the power stoke is where the exhaust valve begins to open. This I have found to be about 30-45 degrees before BDC of the power stroke on most of the cars I have been checking. The waveform pattern (Figure 7) shows the exhaust valve to be opening close to 30 degrees before BDC of the power stroke. The spark was occurring only once in the cylinder when it should have occurred twice. The ignition only fired the waste spark and fired wrong at about 40 degrees after TDC of the

Figure 8 120 MasterTechnician Online | www.mastertechmag.com

exhaust stroke. This was due to the incorrect coil primary control caused by the crank/cam correlation problem.

Known good By viewing a known-good pattern of a 1997 Dodge Caravan with a 3.3L (Figure 8) you can see that the exhaust valve opening event is happening at about 30 degrees before BDC of the power stroke. This file was from a running engine,

so the advance timing was added to the base timing to bring the timing to about 25 degrees (always use the first rise of the inductive clamp square waveform) before TDC of the compression stroke for ignition spark and 25 degrees before TDC of the exhaust stoke for waste spark. This method is such a great way to learn about combustion strategy and, at the same time, give you another weapon in your arsenal to fine tune your diagnostics as far as which direction you want to head in. Even if this had been a dual cam set-up, you would have had no problem in finding out which cam was off from spec without even pulling a timing cover. Just by having this information validated from doing other known-good vehicles, it was safe for me to instruct the garage to pull the transmission and inspect the flywheel. About an hour later the shop called to tell me that the transmission was pulled and I needed to come back to see the damage they found. When I arrived there at the end of my day, I was amazed. The center of the flywheel was completely cut out from the rest of the flywheel like a cookie would be cut out of rolled dough. The center piece spun slightly and wedged itself in place (Figure 9). The

Figure 9

amazing thing was that there was no noise associated with this flywheel while cranking. I helped the garage remove the flywheel and placed it on the ground. I pushed on the center piece and it fell out. The only thing holding these pieces together was the center thrust plate and flywheel bolts. This flywheel was like a wheel of fortune just making the shop spend time and money without a cure in sight, and at the same time sending them on a wild goose chase. It held the torque converter and provided the crank triggers necessary to start the engine. Who would ever think a flywheel could break clean and spin, yet go undetected? I hope this story sheds some light on the value of a scope, which allows you to see beyond the normal reach of a scan tool.

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GM “ U ” B o d y Au t o m a t i c Le v e l Co n t r o l Even though this system is typically trouble-free, it’s on so many vehicles you need to know about it

very so often somebody actually thinks ahead and designs a system to overcome a problem that just might arise. Appearing in two versions on GM’s second and third generation kidhaulers (1997 to current production Venture/Uplander, Transport/ Montana, Terraza and Silhouette, as well as the 2001-2005 Aztec and 2002 and up Rendezvous), the rear122 MasterTechnician Online | www.mastertechmag.com

by Greg McConiga only automatic level control system came about because someone thought about how these famously utilitarian and cavernous family cargo haulers would actually end up being used. I had one, and it transported everyone and everything at one point or another. From fourby-eight sheet stock to ladders and tools, it cheerfully moved everything we stuffed into it while getting about

Here’s what you see with all the fasteners removed and the compressor hanging from its safety bracket. The drier, relay, harness and compressor are in one package.

19 mpg city and 24 highway – not bad for a blunt-nosed, flat-sided aerodynamic nightmare on wheels.

Level’s important Rear level control systems are likely to appear where vehicle loading varies considerably. Large cars with room for three plus-size people in the back

seat are candidates, as well as our topic du jour, the minivan and its SUV spinoffs. If you think about it, you’ll see that automatic rear level control systems are actually safety systems -- crash safety, vehicle dynamics and braking are all dramatically affected by vehicle trim. In a collision, maintaining proper ride height is one key to making June 2009 | MasterTechnician Online

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G M “U” Body Automatic L e v e l C o n t r o l

The ALC relay is mounted to the compressor bracket assembly under the left rear of the vehicle.

sure that all parties involved are properly protected. In a rear hit, a low riding rear bumper could allow the colliding vehicle to ride up over the rear sill and into the cabin area. In a frontal impact, if the front of the van/SUV is tipped up, the colliding vehicle could dive under, perhaps decapitating the occupants or causing an unintended “launch” of the van/ SUV. Additionally, having your tail dragging can bypass the crush and 124 MasterTechnician Online | www.mastertechmag.com

crumple zones that are built around the “normal” impact areas of either front or rear, thus circumventing the impact reducing effects that are engineered into those controlled crush zones. And don’t forget what happens to the headlights! Blinding oncoming drivers is just plain inconsiderate at best, but it’s dangerous to family and friends when you can’t see where you’re going on dark twisty roads because you’ve got the headlights tipped up to the “treetop inspection” setting. Extra weight affects handling even when trim is maintained, and that’s bad enough,

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SHIFT–the way you move

G M â&#x20AC;&#x153;Uâ&#x20AC;? Body Automatic L e v e l C o n t r o l

Hereâ&#x20AC;&#x2122;s the brains of the outfit. The ALC sensor does nearly all the work. The sensor mounts to the body, the non-adjustable arm to the axle and the electronics do the rest.

but tilting the weight distribution rearward and off the front tires makes a mildly under-steering vehicle misbehave even more. Vehicle handling and roll characteristics also change for the worse, as does braking performance. All good reasons to keep the vehicle at or near a standard trim specification.

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There are two variants of the system, one from 1997 until 2002, and another from 2003 through the current model year. Both systems are available with or without the inflator option, which allows you access to the onboard air compressor for chores like pumping up tires or inflatable toys. From 1997 until 2002, the system had no selfdiagnostics, but starting in 2003 a limited self-diagnostic capability was embedded into the height sensor. The actual function of both systems is identical, with the exception of being able to flash codes at the inflator

control switch, and the addition of a circuit to the height sensor that controls the inflator solenoid valve, so we’ll discuss the later system in this article. When working on the first generation system you’ll simply stick to symptom-based diagnostics and follow the appropriate flow chart.

The inflator adds a switch and the inflator control solenoid to the system. With the inflator option you also get limited selfdiagnostic capability.

Click to enlarge.

Components The air shocks are conventional with the addition of a rubber sleeve that’s attached between the dust tube and the reservoir, which creates a flexible air chamber -- you’ll never see them leak unless the boot fails. Minimum residual pressure is maintained at eight psi by the air drier assembly. The shocks are connected to the compressor by plastic lines and couplers that are double o-ringed and

G M â&#x20AC;&#x153;Uâ&#x20AC;? Body Automatic L e v e l C o n t r o l retained by clips. The compressor is a 12 volt permanent magnet DC motor, positive displacement piston compressor with a serviceable cylinder head assembly containing inlet and outlet valves and the exhaust vent solenoid. The compressor is mounted under the left rear corner of the vehicle and is tucked up into the left rear quarter panel area.

The rear shocks are standard design with the exception of the added air bladder. Donâ&#x20AC;&#x2122;t be tempted to replace the air shock system with standard shocks for all the safety reasons previously mentioned. No point in asking for additional liability exposure. 128 MasterTechnician Online | www.mastertechmag.com

The electronic height sensor is the brains of the outfit and attaches to the body while the non-adjustable linkage attaches to the rear axle. The height sensor controls the compressor exhaust valve, the inflator solenoid valve and the compressor, and houses the self-diagnostic electronics and compressor run logic. An inlet filter that limits the ingestion of dirt is a simple foam filter that snaps into a hole in the frame rail. On the discharge side the desiccant-type drier mounts to the top of the compressor assembly between the compressor discharge and the plastic lines that connect to the shocks. On those systems with an inflator system, there is an inflator control panel containing the switch and a high pressure air supply port in the left rear quarter panel under

(Right) The inflator solenoid assembly is mounted on the backside of the inflator control panel, located in the left rear inside quarter of the vehicle. (NOTE: Color is added for viewing enhancement only.)

(Below) Three bolts, one electrical connector and two air connections later and the whole shootinâ&#x20AC;&#x2122; match is on the bench. Be prepared to work a bit to get the bolts loose, remember this thing is right behind the left rear wheel. You can see the compressor ground, the exhaust solenoid in the head, the drier and part of the tabbed bracket that holds it in the frame when the bolts are removed.

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G M “U” Body Automatic L e v e l C o n t r o l a removable cover. The inflator solenoid is attached to the backside of the inflator control panel in the left rear.

Operation At key up the height sensor checks ride height. If it’s within four millimeters of the set point, there’ll be a 30 second wait, then the compressor

runs for four seconds to guarantee adequate reserve air pressure of eight psi. If the vehicle is out of trim, after 20 seconds the compressor will start and run until the desired attitude is reached – or 255 seconds, whichever comes first. The compressor protection portion of the height sensor logic limits run time to 255 seconds at each key cycle to prevent compressor damage in the event of a pressure leak. The start is always

The drier keeps moisture out of line and shocks. Technically it should be replaced periodically, but I didn’t find any published recommendations for replacement.

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G M â&#x20AC;&#x153;Uâ&#x20AC;? Body Automatic L e v e l C o n t r o l delayed 20 seconds from the call for ride height adjustment to compensate for normal vehicle movement and suspension travel, thereby avoiding compressor short cycling or needless starts. The exhaust solenoid valve actuates for 1.5 seconds with each compressor start to reduce pressure in the compressor head cavity and reduce startup current. Located on the left rear inside quarter panel trim the inflator panel has an auxiliary power outlet, the control switch and an air fitting. These vehicles have a hose and inflator kit supplied with them that can stretch to reach all four tires.

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Diagnosis The system has ten DTCs you can call up using the inflator switch. To extract codes, press and hold the accessory inflator switch for three seconds. From initiation the self-test takes 200 seconds to complete. The number of flashes on the switch LED represents the currently present codes and all codes will flash until acknowledged by pressing the inflator switch, or until the module goes to sleep. The LED will flash the first digit of

1- T he foam air filter clips on the end of the intake line and snaps into the frame high up to avoid water ingestion. 2- Rubber splash shield 3- Mounting bracket

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G M “U” Body Automatic L e v e l C o n t r o l the two digit trouble code at half second intervals followed by a one second delay and then the second digit will flash. Each code cycle will be separated by a three second delay. Once the conditions that set the code are repaired, the codes will automatically clear when the ignition is cycled.

Diagnostic Trouble Codes DTC 11 is related to the accessory inflator solenoid, and will set for short to power, short to ground or a malfunctioning solenoid.

DTC 12 is the system okay code. DTC 13 sets if the ride height is out

Real world This system can only be called reliable and robust. Of all the people I spoke with, not one saw any significant failure patterns, which mirrors my experience. We’ve replaced a few lines attacked by rodents (if someone can explain the affinity rodents have for plastic and wiring insulation, I’d sure like to hear it!), and a few shock units that were worn out, or with blown out air bags, but that’s about it. The ability to pump up a flat tire with your own vehicle is a great idea (I’ve done that at least once), and it’s nice to be able pump up pool toys and bike tires as well. It’s a good system that is well executed. Really, I’m on the level!

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of specification.

DTC 21 sets if the compressor relay coil control circuitry shorts to ground.

DTC 22 sets if the compressor relay coil circuitry opens or shorts to battery.

DTC 23 sets if the compressor runs for 255 seconds during a leveling function.

DTC 31 sets if the exhaust solenoid control circuit shorts to ground.

DTC 32 sets if the exhaust solenoid control circuit opens or shorts to battery.

DTC 33 sets if the exhaust solenoid has been energized for 255 seconds and the height sensor did not detect the proper downward movement. As is typical, each of these trouble codes refers you to a multiple-page diagnostic flow chart to accurately complete the diagnosis.

Current issues of Master Technician ONLINE are free of charge to qualified automotive repair shop owners, managers and technicians. Send this website link - www.mastertechmag.com to your tech buddies so they can sign up for their free subscription too!

a mastertechmag.com online publication April 2009

VOL. #15 N0.1

Inside the Insider Five Ways to Limit Liability By stepping out into the business world, every step has exposure. While you cannot stop people from suing, you can insulate your business, personal assets and wallet from most liability if you take some steps to protect yourself. (Turn to page 1)

Human Potential The mind is a strange and powerful tool. Psychologists tell us some very interesting things about its function. First, 90% of its activity is subconscious. (Turn to page 1)

In Times Like These Small business is the skeleton of our economy. Businesses like ours.

(Turn to page 3)

Sole Proprietorship It does not matter whether the individual is just getting started in a new business or is a twenty year business veteran this question comes up on a regular basis. My answer to this dilemma has always been the same, it depends. (Turn to page 6)

MT Business Insider Pricing Matrix

Another Mystery Solved

Needle in a Haystack

Businesses are based on percentages, but customers look at prices. How do you reconcile your business’ need to make a decent profit margin on parts with your customers’ need to pay a fair price? (Turn to page 8)

ASE Certification: The Competitive Advantage One of the most powerful influences on choosing a repair facility is word-ofmouth recommendations from family, friends, and neighbors. Existing customers usually recommend a business based on trust and positive past experience. (Turn to page 10)

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Volume 1 | Issue 1

Five Ways to Limit Liability For Business Owners

By David V. Allen, Esq.

y stepping out into the business world, every step has exposure. While you cannot stop people from suing, you can insulate your business, personal assets and wallet from most liability if you take some steps to protect yourself.

First, incorporate or form a limited liability company. This requires that you file articles of incorporation, or in the case of a limited liability company (LLC), articles of organization with the Secretary of State, or whatever governmental office handles business filings in your state. Once you incorporate or form an LLC, you must hold your business out to the public as a corporation or LLC. This means Continue p.2: Five Ways

Human Potential

Using What You’ve Got

by Greg McConiga

he mind is a strange and powerful tool. Psychologists tell us some very interesting things about its function. First, 90% of its activity is subconscious. Let’s define that. “Sub,” as in “below,” and conscious, as in an individual sense of recognition of things within or without oneself. 90%! Think about that. It says if -- IF -- you are 100% in control during your waking hours, the very best you are capable of achieving is still only 10%. It’s generally agreed that a human’s learning ability is physically unlimited. Remember that a scrap of brain tissue no larger than this “o” can store more information than a computer the size of a Honda. Now, consider that an average person’s brain weighs about three pounds. How many ounces of yours do you actually use? Continue p.5: Potential