These are 2 speed fans. They either both run or are both off, I want to make that clear to you. If you see only 1 fan run, it means the other one is bad, OK?
Alright, these are 2 speed, or have 2 stages. 1st stage (low) is controlled by the A/C system. If the freon pressure is high enough, the low speed fan will come on, there is a relay and a resistor which make the fan run in low speed.
2nd stage (high speed) is controlled by engine temp, I believe on your car it should be switched on at about 105 Celcius. The has a relay also, but no resistor, gets 100% battery voltage to run the fans.
If it seems like the fans never come on, my gut reaction would be both fans are bad. That is, if neither the A/C nor the engine temp will activate the fans.
A simple test is to disconnect the engine temp sensor for the fans, the open circuit (high resistance) simulates an extremely hot engine and closes the high speed fan relay, so the fans should come on "full bore", high speed fan. I'm sorry but I can't remember the exact location of the proper sensor to disconnect, there are a couple different sensors. I know it is on the drivers side of the cylinder head, along side the valve cover. Maybe by trial and error you can locate the proper one. This should work as a test with key on, engine off.
If you have never noticed the fans run with an extremely hot engine, I'd say we are on the right track.
Alternatively, it could be the radiator is plugged internally, which I usually recommend a new radiator, OR the outside of the radiator, the fins, could be bent over in large areas and/or plugged with dirt, bugs, leaves, other plant life, all the other things that make this such a great planet. Between the condensor and radiator is the place to look for this problem, the area can be cleaned out with a garden hose, no high pressure washers as the fins are delicate and can be easily damaged by high pressure.
Last edited by Gilly; 11-09-2001 at 11:57 PM.