My coolent fans on my 1996 firebird are not working. we can get the fans to work by jumping them after removing them from the car. we do not think it is the relay switch. suggestions?

water pump not working or fan belt to slack

Water pump might not be flowing fast enough. Be sure fans actually turn on instead of just sitting there. Change oil. You could have something in the motor causing excessive heat. Piston friction or cam problems ect. Try a synthetic oil.

Most likely a bad coolent temp sensor. To check unplug coolent temp sensor while vehicle is running and see if fans come on. If fan comes on replace coolent temp sensor.

You can do the following with a cold car.

The switch for the electric fan is in the radiator (it responds to the temperature of the water in the radiator, not the temperature of the water in the engine). With the engine running, if the switch has 2 wire on it, pull those two wires and briefly touch them together. If it has only 1 wire, tough that wire to ground. The fan should come on. If it does, the problem is the switch. If not, then the relay or the fan, or the fan's fuse is to blame.

Replace the Blower resistor

the temp sensor is the trigger for the fans!!
the thermostat may be in upside down??
check new thermostat in a pot of water & heat it up watch that it opens up when it heats up should be at aroun 96 degrees F
otherwise the radiator may need a good clean out or a recore!
there my be a blocked water gallery so engine may need a flush aswell
Cheers Rob

The fans don't not come on until 215-225 degrees or unless the ac is on and working. The sensor should be on the intake manifold. See a gm dealer parts dept. for location for which engine you have.

So if you tried another relay & they work, you need a new relay, right?

Does the temperature gauge on your dash work okay?

The coolant temperature sensor provides a signal to the PCM to tell it when to turn the fans on and if its a three wire coolant sensor it also feeds the signal to the gauge on your dash and if the gauge on your dash is not working, it could be a clear sign that the sensor is dead.

However, to start with the simple things, first check the fuses that power the fans, it will be a large fuse probably in the under the hood fuse box and maybe in the 30A range. Check the fan relays as well.

If your car has been running hot because radiator fan inopt.and oily subtance in the coolant, There is a good chance you have leaking head gaskets.