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A vehicle’s electrical system can create some of the most elusive and frustrating repairs. To accompany Motor Age’s extensive electrical system coverage, we’ve asked readers to submit their best (and worst) electrical stories from the bay. Here are a few tales you might be able to relate to.
“A Catholic nun said her 2002 Toyota Camry had been worked on by two dealerships and one independent shop, and the battery still went dead overnight, even after the replacement of the battery, fuel injectors, PCM, alternator and alternator wiring harness, that these other shops said it needed.
A simple amperage draw test confirmed a 2 amp draw at the battery, but I got no further than the fuse box just 10 inches away from the battery — no amp draw there. After pulling the battery, I found the positive lead to the fuse box was being pinched down, (by the battery weight), onto the chassis negative ground cable bolt to the frame.
After relocating this negative connection about 2 inches away, and adding some heavy-duty shrink-wrap insulation to the positive cable, there was no more amperage draw. The next morning the battery had the 12.6 volts I had left it with the day before.
Tunnel vision in any fault diagnostics can kill a business, or in my case, create the biggest account to date — thank you.”
Mark
EquitableAutomotive
Prescott, Ariz.
“Years ago (sometime in 1974), one of my best friends, Randy, got a 1941 Ford Truck, which he “restored” with a new engine, trans, gauges, brakes, everything. Well, he ran into a bit of a problem — seems none of his gauges worked right and the truck wouldn't start. So he called me. It took all of 30 seconds to discover a major problem.
It seems that when he created a completely new wiring harness and hooked everything up, he only used one color of wire, and didn't think it was necessary to put any of those “unsightly” labels on the wires.
Who wants his wires all cluttered up with labels, right? It literally took days to trace each and every one of those blue wires and label them and reconnect them to the correct terminal. This was long before digital multimeters or power probes. He still didn't want to run any sort of color coded wire; he liked his blue wires!
We finally got done and the truck ran fine, but I sure did feel sorry for the guy that eventually bought that truck.”
Bill
“One of the examples I use when explaining to people how hard it can be to find intermittent problems really did happen.
Years ago a customer referred a friend that was having a problem with his battery going dead. The Lincoln Mark had several new batteries and alternators replaced, but the battery still kept going dead…sometimes.
Of course, it would not happen for us, and everything checked out perfect. The customer happened to be a lawyer, and he acted like he was on the witness stand when I asked questions; he seemed to be very unsure about everything I asked.
I had to even call other shops and the dealer because he could not "remember" what they had done. It got to the point I was just about ready to fire him as a customer because he started talking (about) suing people. One time I called and talked with his secretary and she just happened to say, “AAA said they would not go to his cabin anymore because the car was so hard to get to.”
“Wait...you mean this has only happened at his cabin in the mountains?”
“Yep, he goes there on Friday, and when he goes to start the car Sunday evening the battery is dead.”
Why is the car so hard to get to? Because his driveway there is very tight and on a steep incline. “Let me get this straight, this only happens when he is there and the front of the car is parked uphill.”
“Yep that’s right; I don't remember it happening anyplace else.”
It did not take long to figure out the hood mercury switch would turn on the hood light with the hood up about 15 degrees. Just to make sure, we disconnected the light and he never had a problem again. Even after showing the switch and how it worked, he still could not understand why it took so long to figure out such a “simple” thing.”
Jack Skibo
Boradori Automotive
Chico, Calif.
“Years ago, a fellow mechanic was diagnosing an electrical problem with the lights on a Subaru. When the customer would step on the brakes, all the park lights and dash lights would come on.
He spent two to three hours and could not find the problem. He finally swallowed his pride and asked for my help. He had every light hanging out of the fixtures trying to find the problem.
I asked him to step on the brake, and noticed a different appearance of one of the taillights. Apparently the customer had replaced one of the brake/tail light bulbs, an 1157 dual filament, with an 1156 single filament.
This created a feedback through the park light system every time the brakes were applied. It took me 30 seconds to discover the problem, mostly by luck, after he spent hours on it.
He was grateful and embarrassed at the same time. Of course, I never mentioned it again. Right!”
Joel Cox
