can some one tell me why my cooling fans only turn on when I turn A.C. on

 

palma, the fans are controlled by the ECU. If the car is not running hot enough, then the fans will remain off. As for why they come on with the A/C, the ECU is programmed to run the fans at some speed any time the A/C is on. The more A/C, the faster the fans spin.

I am not quite sure what you are wanting to know right now other than what I posted above. If you are overheating while driving down the highway, then you have a problem with your water pump or have low coolant level in the overflow bottle. If you are overheating in city traffic, then odds are you are having your fan controller start to fail on you and you are simply seeing the beginnings of it failing hard on you.

 

thanks thermo