What do you do if the cooling fan will not start on a 1999 Chevy Cavalier?

Answer 1

Under the hood is a fuse panel with a cooling fan fuse and a cooling fan relay. Check that the fuse is not blown, and the relay, you will need to test for continuity between terminals 30 and 87. There should be none. Then with jumper wires and clips connect 12v power to terminal 85 and ground to terminal 86; you should now have continuity. If not, replace the relay. If those two things check out fine, you will have to get to the plug terminals on the fan motor. Connect them strait to the battery. It should turn very fast, If it turns fairly slow or not at all, the motor is fried; get another motor and replace it. And if those things are good, check/change the coolant temp sensor. If all that checks O.K. then you have a problem in the wiring. Check the wiring from the relay going to the computer (inside right front fender) for any shorts or breaks. Just guessing without looking at the car that it will be the fan motor.

If ALL of those items are good, the only thing left is the ECM itself, but the fan speed is very crucial. Just because you think it is going fast doesn't mean it's going fast enough.