I had the weirdest thing happen. When I jumped a wire across the A and B ports for checking the trouble codes, one or both of my fans turned on. I was able to retrieve the trouble codes (which was 12 so really there were none) but I'm quite concerned as to why this has happened. When I took off the jumper, the fans turned off. When I started the car, the fan turned on again. When I started it a second time, it was off. The car was cold by the way. I feel like everything is ok now but has anyone experienced this? My car is an 89 GTA, 5.0 TPI w/ manual trans.

 

was your AC on? the fan comes on then.

Really you have nothing to worry about as long as your fans come on when your car gets hot or your AC is on. Dont worry about it

 

AC was not on. In fact, it does not work anyway. That is the next problem I have to tackle. I just hate the fact that everytime I check the codes the fans will come on. I have done this on GM vehicles many times and have never seen this problem.

 

AFAIK the fans turn on with any thirdgen that has an electric fan. Just FYI I have checked practically brand new thirdgens with a paper clip and the fans came on, so no its not something that changed through wear or ownership.