My Driver's side fan works as soon as the AC is truned on and also when the car hits a certain temp with the AC off. The passenger side does not work. I have tested the passenger motor, it works fine. Last night I used a jumper wire to test between the two wires that go on the thermofan switch - only the Driver's side fan went on. Any suggestions -

Jeremy
1983 Guards Red

 

both fans are fed from separate fuses. If not the fuse check the relay.

 

Jeremy:

You have tested the LH fan. Run a wire from the battery to the fan (one contact) and then to ground (second contact). This can be a more or less permanent way around a broken circuit. From the battery (through a fuse) to the thermo switch; to the motor. You will not have a dropping resistor (you can put one in series) and the fan will run whether the key is on or off if the thermoswitch is closed. You would run this through a relay, bridging the relay with the dropping resistor. This way when the key is on (relay is switched with the ignition), you get full current to the fan. When the relay is open, reduced current flows through the resistor until the thermoswitch opens. I did this on my old 924, even adding an indicator light to the dash to tell me if the fan was on or off. I mounted the relay above the radiator on the cross member, and built a plastic shield to protect it from rain and crud. I sold the car two years ago and the system had been working properly for six years.

Good luck!!

Bob S. (loves indicator lights...look neat on the dash)