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Article: Joe Friday Diagnostics - AGE check--remember Dragnet with Sgt. Joe Friday? Here's my version of the Sarge diagnosing a carJoe Friday Diagnostics "How would Sgt. Friday explain auto repair and diagnostics… que the music: " The story you’re about to read is true; the names have been changed to protect the innocent. Monday morning, it was cold that day. I was working day shift out of the repair division. There’s a suspicious vehicle at the front of the shop. A customer walks in the door. I’ll take it from here. I’m a mechanic, the name’s Friday. It was a 2003 Ford, 5.4 liter, fully loaded and sounded like it was running rough. The lady came to the counter. “Good Morning ma’am, what can I do for you,” I said to the complaintant. “Yes, I’m here about my car,” she answered. “There’s a problem with the car, I see. What can you tell me about it?” I asked, in my usual non-threatening, but confident monotone voice. “I was on my way to deliver my recyclables to the east side collection area, because I’m a concerned citizen you know, when my car started to make a coughing and clattering sound. I thought I would bring it in to have it checked out,” the owner answered. “Coughing and clattering, hmm, not a problem. I’ll get it investigated, I can interrogate the pursuant this morning, especially for a concerned citizen such as yourself,” I answered while maintaining my professionalism. “Well, do you need any other information from me?” she asked. “Just the facts ma’am, just the facts,” I said. “The check engine light came on,” she reported. “This could be of some help. Sounds like a possible 0300 (engine misfire). But I’ll check it out first, I’ll need to finish my investigation in order to give you any proper results,” I said to her, while my pen was busy jotting down the facts onto the always present handy notepad. She left the car with me for further interrogations. Using the scanner made the results easy to locate. It wasn’t long before I got an answer. It was a P0302 in progress… misfire on no#2 cylinder… normally an open and shut case. 09:30 Am, working on the assumption that the perpetrator was somewhere near the 2nd cylinder; I went in for further investigations. I checked the usual suspects. Pulling the plug didn’t yield any new clues. The plug was good and answered all the standard questions. The coil was a more likely suspect; a simple test could answer the problem. I’ll set up a little sting operation by using a decoy. Taking the nearest coil and replacing it with the suspected faulty coil, and put the known good coil on the other plug. I was hoping to see the miss move to the other cylinder. It didn’t. In fact it was gone. 10:05 Am, Now the challenge was on. I’ll have to go back over my facts and check the crime scene again. There’s something I must have overlooked that might be the key to this investigation. Two things come up as good possibles; the connection or terminals at the coil, or the spark plug boot attached to the coil. The plug boot had a good alibi… it had just been changed, in fact so was the spark plug. That left the coil connection. A more in-depth interrogation of the connector is needed. My years of technical diagnostics work told me to look closer at the wire and the connector. The guilty party in this case appears to be one of the wires at the connector. It was barely hanging onto the housing. Only the plastic sheath was still connected, and the wire itself was not answering to any of the standard questioning or interrogative tactics. Under the intense glow of the high powered shop light the investigation continued. Resorting to some strong arm tactics I pulled on the wire while using a few choice investigative words, the plastic sheathing kept getting longer and longer. Soon, it snapped under the pressure to expose the desperado for the perpetrator it really was. 11:45 Am, The repair was completed, and tested to verify the repairs were effective. The car in question was back with its rightful owner by the end of the day. I now can close the file on this one, another job well done. In conclusion: With the P0302 in question deleted from the computer history, the coil connector was then convicted of failure to cooperate. With her car back on the road she could once again be a productive concerned citizen of this great metropolis. Case closed and now, back to the front desk waiting for that next problem to come through the door. This city is full of broken, non-maintained, and poorly running cars. As a concerned citizen I’ll be on the lookout for these suspicious misfires and other infractions of the auto world. There are thousands of men and women in this city, who know that being an auto tech is an thankless, grease covered job that's done everyday without any fan fare. Then again, I'm part of that glamourless, grease covered world... my names Friday, I'm a mechanic.
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Article: Ouija Board Diagnostics - You're doing it wrong if your Ouija board is your go to diagnostic toolOuija Board Diagnostics I’ve often wondered why a lot of the driving public believes auto repair is something for non-thinking Neanderthals that have no ambition to do anything else in life. For all I know they think we (us mechanics that is) diagnose every problem by breaking out a Ouija board, while humming some ancient automotive chant. It could also be that a good mechanic just makes things look easy to the unaware and uniformed layman. With the right mechanic the whole thing can seem effortless, easy, and somewhat second nature when it comes to diagnosing a problem. To the armchair mechanic sitting at home watching the next new automotive reality show, it’s either – “Repairs are a no-brainer, I can do that”, or it must be some sort of Ouija board magic. Mind you, the number of individuals who still believe anyone can be a mechanic is dwindling ever so slowly. Mainly because the car itself has gone past the point of parts swapping and a shade tree mechanic’s ability to repair the modern car. It’s no secret good old dad with the typical box of tools from a discount chain store can hardly change a spark plug anymore, let alone find them. Oh sure, you can still do a pad slap at home, and you can probably toss on a set of shocks, replace a bulb or two, but diagnosing a problem, especially one that involves some form of electronics… well… that’s a whole new issue to deal with. It could be they need to master the Ouija board diagnostic scenario, or they need another round of You Tube videos. Every mechanic has undoubtedly heard the same thing from a well-seasoned You Tuber, “Oh I could have done that.” This usually leads to an even longer explanation of how you’ve done the entire repair wrong, but put the tools in their hands, and the results are pretty consistent. The car is either incorrectly put together, or they’ve lost some parts between point A and point B. Videos are great, but you still need to have some mechanical dexterity. A good example of this scenario is when I was teaching a brake shoe replacement class the other day. After explaining the type of brake system we were working on, I removed the brake shoes from the car. Next, I reinstalled the same shoes, slowing down just enough so they could see how to use the brake tools. It probably took all of 20 minutes to explain it in detail and install the shoes. All the heads were bobbing and the usual consensus was they all had this repair procedure down pat, because, as we all know, anybody can do brakes. Well, as if it was no surprise, when the students got their hands into the job all I heard was one cuss word after another and the occasional student chasing a bouncing spring or clip across the shop floor. So much for easy, aye? So, where do most of these unprofessional type mechanics and couch connoisseurs of the automotive world go for any information? Where else, the internet. The one place that doesn’t check the credentials of the person making the video, and the one place where anyone with a box of tools can be a superstar with a wrench. In their video they’re the automotive expert, camera man, sound man, director of content, and editor all at the same time. No need in researching the facts, looking up the proper methods, or any other various procedures, service bulletins, or the latest tools related to that particular job. I wouldn’t be surprised if there’s a video out there with a couple of guys surrounding one of those Ouija boards asking why the short fuel trim is higher on one of side than the other. Ouija board or not, there are a few draw backs to internet information, but there really are a lot of super fantastic guys and gals putting out some very helpful videos on car repair. It’s just the few home brewed videos that make me cringe. Some of these back yard magicians seem to consult their Ouija board way too often. As if they conjured up some miracle answer right on the spot. Honestly, some of these videos are about as reliable as fake news. But, then again… that’s what some people think the professional mechanic does every day. As there has always been, and there will always be, a shortage of trained technicians out there able to handle the job of repairing the modern car. I’m very sure we will never see the day when there is an overabundance of good mechanics who have to change careers because there is no room for them under the hood. It’s never going to happen. What does need to happen is the one thing consumers don’t want, and that’s cost of repairs most certainly need to rise, as well as the mechanics’ wages to keep up with all of these technical advancements. It’s not a maybe, it’s a must or the technology will run right past you. Ask any mechanic what they learned on a vehicle from 10 years ago vs. today’s cars, and you’ll find that nearly half of what they did back then isn’t applicable in today’s diagnostic procedures. To be a good technician these days takes a lot of training, a lot of time spent reading, and understanding the latest technologies. New information comes from the manufacturers’ engineering departments just as fast as the cars come off the assembly lines, and to stay on top of things you need to study. I’ve heard people tell me, “Yea, I went to an automotive tech school to be a mechanic, but I didn’t learn anything.” Seriously? I’m sure you learned a whole lot. The problem isn’t the school training, the problem is you. Training doesn’t stop with your diploma, it stops when you stop wanting to advance your knowledge in the repair industry. School is a starting point, but to be a modern mechanic means you need to stay focused on the technology, take advanced training classes in your field of choice, and not expect answers from a You Tube video or your Ouija board. There’s a lot to learn and retain. It’s not a trade where you learn one method and expect that skill to last you throughout your career. It’s an ever changing industry with ever changing technology. Learn the basics, then learn to diagnose the modern car. You can’t guess at a solution or consult that old Ouija board for the answers. It takes practice and a lot of hands on from a dedicated individual willing to get their hands dirty and diagnose an automotive problem. Then solve it correctly. Sorry, no Ouija board diagnostics allowed.
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First, The basics Let’s talk diagnostics. Do you follow any kind of diagnostic procedure, or do you just throw darts on a wall, or play “pick-a-part” and hope you fix it before you or the customer runs out of cash. I hope you don’t do that. That might work some of the time, but it’s not a good way to get to the source of problems quickly or accurately. One of the tire shops that I do business with dropped off a 2003 F450 with a 7.3 diesel for me to look at. It’s one of their service trucks that died on the highway. These guys are super, I’ve known them for years, and they’ve got a great reputation and excellent work force. In fact, I buy all my tires there, and they do all my alignments. They try to fix their own trucks “in-house” and sometimes, well……the repair/diagnostics are a little out of their comfort zone. This was one of those times. Now, they don’t try to keep up with the scanning or diagnostics on most cars and trucks. It’s a tire shop that specializes in tires. They stick to what they do best, tires, wheels, and undercarriage stuff. The only “techy” stuff they get into is with the TPM systems. Most generally, when it comes to their vehicles they’ll go with the tried and true…”throw a dart and whatever it hits we’ll change.” Of course they’ll ask around first, but you know, second hand information hardly ever gets the job done these days. They had it at one of their stores in another town for about 3 weeks trying to solve the problem. When that didn’t work they decided to tow it up to another one of their stores, and see if the guys there had a better dart. Another couple of weeks and several darts later, all they had were holes in the wall and no truck running. Then my phone rang. “Can you program a PCM on a F450?” the shop asked. “No, sorry I don’t do those, but I know who does. I’ll call him and see if he can come over and do that for you,” I told them. A day or two went by and the phone rang again. “Hey, this thing still doesn’t start. The guy that programmed it said it sounded like an electrical problem”. Ok, somehow, I’m getting involved now. “Sure, bring it over,” I told them. Well, they towed it over with a strap pulled by an F250 diesel truck. The F250 looked like a toy truck compared to this behemoth. With a push and a shove from the F250 the guys got it lined up and into one of my service bays. The big concern was the IDM relay, it kept chattering like a machine gun. Instead of checking codes I thought it best just to start with a complete wire to wire check to determine if there was some lost signal that was causing the problem, or a wire that was scraped and grounding out. Removing the inner fender on the driver side I could gain access to the Injector module (IDM) and the PCM (Power control module). Seemed easier to start here than any place else. It didn’t take long before I tracked down a problem. On pin #71 of the (new) PCM there should have been 12 volts from the ignition. No voltage at the terminal. Tracing the wiring diagram thru its maze it led back to the in-car fuse box on fuse #22. I grabbed my test light and checked the fuse… (Rolling my eyes about now) the fuse,… oh man… the fuse is blown. Good grief… all this for a blown fuse. Well, I better change the fuse, and see if it starts. Sure enough; it fired right up… sounded great, good throttle response, and no service lights. Now the big challenge, what blew the fuse in the first place? Following the wiring diagram again…. I traced out all the components on the fuse circuit. There was one that caught my eye as the likely culprit. The brake cut-off switch mounted on the master cylinder. (It’s the one that had the big recall a few years ago.) The updated replacement piece was in place but somebody forgot to secure the wires. The replacement piece has a newer style connector and an adapter connector to allow you to attach it to the original style fastener. Which makes it a little longer than it originally was from the factory. It was hard to tell where the new wire and connector started, and the old one ended, because the whole thing was lying on the exhaust manifold, and had melted down to a glob of wire and plastic. Looking around under the hood there were all kinds of new parts installed. The nicest part……they were all installed correctly. There were no other wires out of place, or any signs of scraps or melted wiring. The important thing is that it runs, and the truck can go back to doing what it needs to do. I think the biggest thing that threw everyone on this job was the chattering relay. It sounded bad, sounded expensive… but, all it turned out to be was a loss of proper voltage to the PCM, because a fuse blew from a lead that grounded out. This was due to the improper installation of one small component. The PCM couldn’t spread enough voltage and ground signals to all the necessary systems when it was missing the voltage it needed. As the relay would engage, the voltage drop was too much to keep the relay engaged. The IDM would pull more signal voltage as the relay would come to life. Then the PCM would have to drop the ground signal to the IDM relay to compensate for the loss of voltage. All this was going on very rapidly … on and off, on and off… making the machine gun sound coming from the IDM relay. The guys at the tire store were extremely grateful that I got the job done, so they could use the truck again. For me, it’s another day at the shop. I’ve got nothing but good things to say about the guys at the tire shop. Hey they tried, I’ll give them that. But one thing I wish they would do next time --- CHECK THE BASICS—BEFORE BUYING PARTS! It’s cheaper that way…
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Water Cooler Diagnostics We’ve all heard the phrase, “codes don’t fix cars, good diagnostics does”. Codes are merely a direction or path, not the answer as some might think. Those “codes fix it all” believers are usually at the bottom of the diagnostic chain. You know the type; those Neanderthals with little wrenches and big cheater bars, or the ones that follow the old adage, “When in doubt-rip it out” method of diagnosing a problem. It’s seems to me that car repair for a certain demographic of people has always been something related to hand-me-down repair information, not diagnostic skills. I believe it’s all because of the availability of cheaply made parts and bad information. Some of it is hearsay, but a lot of it comes from two guys chatting next to the water cooler at work, and neither one of them have any automotive diagnostics background at all. This latest case study is a perfect example of why swapping parts and paying attention to those water cooler experts isn’t always a good idea. A trained technician with diagnostic background and less time at the water cooler may be what you need. A 2007 Dodge 4.7L pickup came into the shop with a stalling problem. The owner had already stopped by the water cooler and made a trip to the code fairy. Since no codes were stored, there wasn’t much for him to do except follow the water cooler genius’ advice. He swapped out every sensor and computer part he was told about and a few more he could barely reach, just to be safe. All of which didn’t change a thing. Before writing up the work order, I had to listen to his story, which ended like most of them do, "I've already spent too much on this truck, and I don't want to spend a penny more." (I wonder what kind of commission the water cooler guy got from the part store for helping this guy spend all his cash.) The stalling was pretty predictable, usually every 15 minutes. Just as it would stall, the check engine light would rapidly flash, then the truck would sit silent. If you turned the key off and back on, the truck would run perfectly as if nothing happened, right up to the very moment the whole scenario repeated itself. Since the only odd thing was this momentary flashing of the MIL, I decided to hook up a scanner and wait to see if this odd failure would show up on the screen. Sure enough, code P0688 popped up momentarily, just as the truck stalled “ASD signal low”. Out of habit I reached up and cycled the key. Dang it, the code never stored and the truck is back to running correctly again. I’ll have to wait one more time and see if I actually had the right code number. Since it only occurred as it went through its death roll, catching this failure was going to be tricky. It was the correct code alright, but no signs of dropped voltage or weak connections anywhere to be found. It’s time to pull out the big guns. Break out the scope boys! With the scope hooked up to two different injector leads and the remaining channels on a couple of coils, I spent the afternoon watching the ASD voltage like a nervous hen watching her chicks. As if on cue, the truck died. Not a bit of change on the scope. I’m definitely going at this the wrong way. Something is dropping off, or at least I assumed it was. Instead of looking at the ASD signal, how about checking the injection signal and coil signals from the PCM? This time the scope did have a weird response. Just as it stalled there was a little extra squiggly line that didn’t belong in the pattern on the coil input leads. Very subtle difference, but enough of a difference that it needed closer attention. The voltage signal spiked a bit higher than normal just as the truck would stall, and then the voltage would drop to zero. It must be the PCM or a coil. Since the signal was only there for a brief blip on the scope, it wasn’t exactly something I could put my finger on just yet. Time for some old school tricks. Since the PCM was new, I could at least (with some trepidation) rule it out for now. I could test further, or I could try to create a problem that might mimic what I was seeing on the scope pattern, or with luck, if it was a spike that was coming from a coil, disconnecting it could show the problem. I decided to give this truck a miss of my very own and see if I could increase that little squiggle into a bigger one. I'll unplug one coil and watch the scope pattern. If I’m lucky, the truck will either stay running longer than it normally did, or it might show me a larger voltage spike. Sure enough, I found it on the third coil. As long as that particular coil was left unplugged, the truck ran well past the usual stall time. To verify it, I plugged the coil back in and watched the scope readings directly at that coil. A millisecond before the stall the coil spiked to the top of the screen as the truck shut off. Just as I suspected, if it was on the coil that was causing the problem the spiked voltage would show higher there than on the adjacent coils. The big question for me was why did it not set a code? The reason was the coil lead led straight to the PCM. The extra high voltage going back into the circuit simply turned the PCM off as if the key was turned off. There’s no codes for shutting the truck off, only codes for failures that make it shut off. The solution...replace the coil. Now and then there are problems that don’t follow the diagnostic steps laid out by the engineers. Even though you’d think every aspect and every type of condition has been tried and tested, or at least talked about around the water cooler. There are times when you’ve got to look past the “assumed” problem and dig a little deeper to find the cause. There's no doubt this repair is going to be another one of those conversations around the water cooler, but I seriously doubt anywhere in this story will the novice know-it-all admit that it took an experienced technician to locate his problem, not his water cooler buddy. Oh, and I don’t expect to hear him say as he leans on the cooler, “Codes don’t fix cars, mechanics do” even when there isn't a code.
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One diagnostics, two diagnostics, three
The budget conscience customer at a repair shop asks, “Why do you charge so much for diagnosing a car? The machine does all the work. I’d rather just take my car to one of those places that offer free code checks.” The mechanics answered, “If those “machines” do all the work and those free places can tell you what’s wrong, why are you here?” It’s the typical song and dance of the one diagnostics, two diagnostics, three.
Apparently, I was misinformed as to how or what knowledge is necessary to diagnose the modern car. It seems, to some people, that all you have to do is hook up a scanner and the answer pops out like bread in a toaster. If so, why do most of these folks that head for these free code jockeys, still end up going to next read-code-change-part shops before a “real” mechanic finally figures out the problem?
Of course, you have to consider where this information about diagnostics is coming from. It’s a safe bet that neither captain code reader or his first mate cheap skate customer, have any high opinions that a trained professional mechanic is needed to find out what’s wrong with the land yacht. The opinions vary, but you can basically whittle them down to just three variations especially when it comes to diagnostics.
A – “All mechanics are alike”
B – “Always go with the cheapest mechanic you can find because they all have the same scanners and tools.”
C – Combine A and B.
It’s the term “diagnostics” that has several different meanings too. The charge for the diagnostics is always a question that someone will have, but I’ve never had anyone ask me, “What makes your diagnostics better than the next guys?” Just in case I ever had to answer that question, I’ve divided up this song and dance of diagnostics into three categories. So here goes, diagnostics, and a one, and a two and a three….
1. Be the code commander at one of those “free read” places, and grab your low-end-can’t-do-much-else-but-read-generic-codes and give your interpretation of what the display is telling you after your brief instructional lesson on the use of the tool to an even less informed consumer.
2. Be a code jockey at a more professional shop than your local parts store code commander ever could possibly imagine of being, and grab your high end scanner but only to use it like a code reader.
3. Actually testing the component or system that is coded and determining what the failure is with the aid of a scanner and other various tools of the trade.
The big problem that I see is that some people that have the same misconceptions that all mechanics are equally trained also have mistakenly determined that all scan tools are the same. Code reading is one thing, giving your opinion of the meaning of said code is another. Trying to diagnose by just reading a code is the real problem.
It still surprises me when someone questions the diagnostic fee, or asks, “Now you’re going to take that off the bill if I have the work done right?” Answer that question with a no and you’re liable to see a majority of those type of customers walk out the door. Say yes to the question and you’re into a situation that after you’ve spent time on finding the source of the problem that the estimated repair is going to run more than the customer wants to put into the car, and now they decide not to have the work done. All the time you just spent on the car is lost dollars that you’ll never recover.
I’ve tried it both ways over the years and I’ve come to the conclusion that I’m better off getting paid for the use of my scanners, diagnostic charts, meters, scopes, and various other tools needed to perform the correct procedures and tests than I am of letting all my efforts slip out the lobby door.
What’s the solution? Everybody has their own opinion as to what works better. Quite frankly, I think the only way it will ever change is with time. When enough time has passed and less and less repairs can be made without solid and proper diagnostics maybe then it won’t be such a big hassle.
For the here and now, maybe I should offer diagnostics as a “One, and a two, and a three” types of diagnostics. But, I’m no jockey and I’d make a terrible captain so I might offer different code diagnostics but that doesn’t mean I’m going to like it.
As it is now, most everything such as turn signals, engine performance, theft systems and the like all go through more than one computer module. Coding is taking on a whole new era of diagnostics. One thing can lead to two and two can lead to three. That’s where more in-depth diagnostics plays a major part in solving an issue with the modern car more than just read a code.
I wouldn’t put it passed the engineers to monitor balljoint wear with a sensor, or even tie rod ends in the near future either. All those wearable items on a car could eventually be monitored in some form or fashion. Then, when a car comes in for a front end alignment it won’t be so much the technician putting it on the alignment machine right off the bat, they would have to start the diagnostics off with a scanner. There would be less of the customer coming in that tells the mechanic that the last shop said they needed a laundry list of suspension parts when nothing checks bad at the next shop.
For the most part, if you’re reading this and you’re a shop owner or tech you’re probably nodding your head right about now. You’re probably saying to yourself, “Been there, done that.” Yea, “we” know what it takes to diagnose some of these problems but what “we” need to let every consumer know that it takes more than a code jockey or captain code reader to diagnose their car. Diagnostics isn’t as simple as “A one, and a two, and a three”.
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