Got in my truck last Sunday and turned the key and was rewarded with a resounding click. Click? That's not good. Truck is ten years old, the battery has been replaced once, and with the way batteries fail these days (One day they are fine and the next they are kaput. It's not a gradual process any more.) it's probably time for a new one. I try jump starting it, but no help. Let the cables stay connected to the car-car's battery for a minute while it is running just in case, you know, the truck battery is really dead. No help. Get the VOM (Volt-Ohm-Meter) out. Battery shows 13 volts. Wedge the leads in the battery cable fittings and turn the key. Big fat click and the needle doesn't budge: rock steady at 13 volts. Okay, it's not the battery, it must be the starter. I suspect the contacts in the solenoid are probably shot. Give it a few more tries and it finally starts. Take it down to the shop and leave it with them.
They get around to sorting it out a couple of days later. Turns out it was just corrosion on the battery terminals. On one hand I am really embarrassed, I saw a bunch of green corrosion growing around the positive terminal, but I didn't figure it was a problem. Used to be (30-40 years ago) corroded battery terminals were the number one cause of starter problems with cars, but I haven't seen a terminal that was corroded enough to cause trouble since I don't know when. On the other hand, it doesn't make any sense. The meter was connected on starter side of the battery terminals, it wasn't connected to the posts, so the corrosion was between the meter and the battery. When I turned the key, the voltage should have dropped to zero, but it didn't. Something funny going on here. But it's working now, so I guess I shouldn't worry about it too much. Bugs me though.
They also fixed the flakey turn signal. The left blinker started flashing very fast a couple of weeks ago. Both front and rear bulbs are working, so I'm thinking there is a short in the wiring, either in the dinged front fender or in the tilt steering column. I read about that last one on the internet. The mechanics tell me they replaced a couple of bulbs and now it's fixed. This is another one I don't understand.
The blinker is essentially a resistive bimetallic strip. As current flows through it, the resistance causes it to heat up, the heat causes it to curl, and when it curls it breaks contact, the flow of current is interrupted, the light goes out, the strip cools off, it uncurls and finally makes contact again and the cycle repeats. The making and breaking of the contact is what gives you the tick-tick sound that goes along with the blinker. (Oops, wrong again. No bimetallic strip, simple heat expansion of spring steel. Should have known the auto industry would find a cheaper solution than using fancy bi-metal strips. Or at least that's what HowStuffWorks claims .)
If a bulb is burned out, less current will flow, and the blinker should blink slower. If you have a wire that is shorted to ground somewhere, more current will flow and the blinker will blink faster. Both lights were blinking much too fast, they changed the bulbs and now the lights are blinking at the correct rate. I don't get it. Changing light bulbs should not have had any effect.
Lastly, the automatic transmission needed two (!) quarts of fluid. There is no sign of a leak, so where did it go? I had another car that did this and it was caused by busted diaphragm in the vacuum operated downshift control. The engine was sucking the ATF up the vacuum line and burning it. No leak, but the fluid was disappearing. That's my suspect right now, but after these other two problems, I am not so sure I know anything about cars anymore.
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