I am having electrical problems in my used Rainier. When I first got it 5 months ago, it started having random and inconsistent issues. The passenger side window would roll down, but not up for a few days, but works just fine now. I turned the car off, and got out only to notice that the radio was still playing once. Now it turns off when the door opens as it should. The next day I got out and the car was off, and the driver's side electrical rear view mirror was moving all over the place on it's own. It hasn't done this again. The "check air bag" light is on. I had a mechanic look at it, and he said that the air bags must not be working. He checked in my driver's side door to see if any cords were loose, but there didn't seem to be any issues. Also, the horn works when pushed on the stearing wheel, but it stopped working (used to work) when I push the lock button twice on the key fob. Finally, the radio has started to occasionally have a squealing noise, not matter if I have the radio, AUX, or a CD playing, but quits for weeks at a time. I skimmed a little bit online, and see that some people have similar issues. One thread mentioned something about anti-electric lubricant under the car or something? I am hoping someone can give me step by step directions for how to fix it or at least check the problem. I already put quite a bit into the car because the engine wasnt heating enough, and the airbag fix alone was quoted at $400. I have done similar minor repairs of old vehicles. Hoping I can fix this one myself.

 

 

I agree with Rich B..
Keep in mind that the electrical circuits operate on millivolts and the slightest variation especially sent to the wrong place can produce results that are difficult to explain. If you cannot find any unusual, dirty or corroded connections, it may require a high end scan tool to check for any possible codes in the system that might provide some direction.. The scan tool can run a "health check" of the modules and possibly come up with an area to pursue further.

We call these occurrences Gremlins, and sometimes a Soft reset gets rid of them.
A soft reset is when we remove the negative battery cable from the negative mounting at the battery and connect a piece of wire from the disconnected cable end to the positive cable. This allows some of the memory to get lost . Things like memory radio stations , memory seat, memory mirrors etc have to be reset, but if you have Gremlins in there they get lost too. If you think you would like to try this let us know, thanks.