Heading for work one morning, my C5 Corvette (1997-2004) ran terrible. When I headed home, it behaved the same way. The next day it wouldn’t do anything but flash the dash lights when I attempted to start it. The car has a self diagnostic system that can be accessed by pushing the correct display buttons, but this didn't work either.
Fortunately, I knew about an Internet forum for Corvettes that's loaded with all kinds of information, especially on fixing problems.
This forum is very helpful for those owners who are far from large cities, since small dealerships don’t sell many Corvettes, and consequently, their service technicians are not experienced with these vehicles. The forum included several stories of technicians simply “throwing parts” at a problem, hoping that the bad component ended up getting replaced. Meanwhile, the owner pays for everything, and the replacement parts are very expensive.
There is one service technician who participates on the forum who has a great deal of experience with Corvettes. He suggested that I remove the ignition switch, take the unit apart, and look for bad electrical contacts inside. He also provided a link to a previous post of his in which he provided step-by-step disassembly instructions, a repair procedure, and photographs.
Sure enough, after I disassembled the switch, I found that two of the five electrical contacts were coated with a black substance, while a third was one-quarter coated. After careful “sanding” with 2000 grit paper and an alcohol cleaning, I re-assembled the switch and everything started and behaved as normal. So, what could have been a repair bill close to $1,000 was fixed at no cost, in an hour.
This entry was submitted by Bob Salter and edited by Rob Spiegel.
Bob Salter is a mechanical engineer who works for American Roller Bearing Company. He is also a dedicated do-it-yourselfer.
Tell us your experience in solving a knotty engineering problem. Send stories to Rob Spiegel for Sherlock Ohms.
Bob, it is very common for auto mechanics to "throw parts" at a problem. Actually, I found when I was working on my own cars (typically old British sports cars), I did it myself, since they were not easy to diagnose. That is why we often collected old cars and parts, so it generally did not cost a lot. We also did not have the on-line forums.
I have to agree with comments so far – Mechanics often play it safe, and replace parts – not to intentionally run up the bill (as my Wife speculates) – but, because they can't find the real root cause issue; and then they justify it with statements like, "well, that element had a lot of corrosion, and would have need replacing SOON, anyway -so- better safe than sorry". The much more frugal side of me has often frequented On-line blogs and boards to find better clues.
Love your story Bob. I too do a lot of my own car repairs (I own a 33-year-old car). Usually, whatever repair I need to do has been done by someone else who has posted step-by-step instructions, often with a video. This Internet thing is great. I hope it sticks around.
The potential $1,000 figure quoted in the article is probably not very far off. Having the ability to do the repairs yourself is huge, given the cost of parts on many of today's vehicles. Even more so on the 'Vette, which, according to Consumer Reports, has only an average reliability rating for models between 2006 and 2011.
One thing that I learned with this episode is that the modern computer controlled automobiles are sometimes very difficult to troubleshoot. Sure, one can push some buttons on the Corvette's dash to troubleshoot, which is more than one can do with most newer automobiles, but other maladies can prevent the system from working. Bad ground connections, usually from corrosion, and low battery voltage can often disable the computers. These were checked first. In my case, the two computers, Power Control Module (PCM) and Body Control Module (BCM) seemed to have enough voltage to operate a relay (clicking sound) and flash the dash lights, in sync. However the BCM didn't have the ability to read the resistance of the pellet in the key to satisfy the security system. But, a couple times it did as the engine would crank but not fire. Each GM dealership should have a diagnostic computer called a Tech II for trouble shooting, but this is still no guarrantee of identifying the root cause of the problem. The gentlman that helped myself and others is a GM certified technician, and the way he identified the problem was experience. He recommended that a previous Corvette owner with the same problem replace the ignition switch on a hunch, which solved this owner's problem. He was good enough to send the faulty switch to the technician, who disassembled it, observed the contacts, and figured out how to fix them. My good fortune is that he shared this insight on the forum. This epsisode reinforces my long time theory that experience in auto repair is the best diagnostic tool.
The internet is a true wonder of communication. Lately, I have seen use of the internet as one of the best tools in my tool box. The work of fixing the problem is not hard part. Knowing how to fix the problem is the big problem.
I ran the Factory Service Department for an Agricultural Electronics business for a number of years. Part of the troubleshooting process for many technicians was to replace parts and see if the symptom went away. I always cautioned against that type of repair and demonstrated scenarios that would result in many parts being replaced without the root cause being found. Rarely would semiconductors fail, but an unskilled technician would always replace the largest, most complicated component first. The technician that used an oscilloscope to find the actual failure not only benefited the customer but also the company by finding problems that may have been in the design.
I agree, Tim - the internet is a HUGE resource. I have used online forums to get information from programming a PIC microcontroller to fixing a plumbing problem to figuring out the best approach when one of my horses decided to misbehave. The first thing I do when I have a question (after I have completed preliminary research) is to search for a forum online to get help. We have to keep in mind that anyone can write anything in cyberspace, but it is usually pretty easy to establish credibility just by using common sense. That was an awesome fix on the corvette thanks to forum help and some initiative on the part of the owner.
I had a Mercury Sable wagon once, probably a mid 90s model, I forget. One day the driver side window switch just stopped working. I called the dealer and he wanted about $600, installed. I went to the local junk yard and they wanted something less, but not by much, indicating that this was a high-failure part and much in demand. So, i decided to at least SEE what might be wrong. I took the switch assembly out and noticed it had CB-point style dry contacts and that these were hefty enough to run the main motor current through. They were heavily pitted and oxidized over, hence the lack of operation. I dismatled the switch so I could clean the points and in doing so noticed that the PCB to which the switch assembly was wired, had pads for spark suppression capacitors on it. They were unpopulated... The engineers HAD foreseen this problem, made provisions to correct for it and the bean-counters (I am guessing) did away with them... I put in caps and NEVER heard from that part of the car again. SEVERAL other things went bad electrically with that car, prompting me to sell it. I always wonder what more was removed as unessential in the interests of cost-management...?
Great story Bob. I too had a problem with the ignition switch of my 2001 C5 coupe. While you were doing your research, you may have read my posts in the Corvette forum documenting my troubleshooting and repair . I had posted schematics in the forum to explain the process I went through to find the problem. To confirm the ignition switch was at fault, I jumpered between two fuses on one of the fuse blocks. The problem disappeared and the car functioned perfectly so I took the dash apart and headed off to the Chevy dealer to buy a new switch.
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