aux temp switches

[Infamouscrew02]

Does the ac button have to be turned on for the aux temp switches to work?

I installed a electric fan to be ran by these temp switches and it never turned on when i warmed up the car. So its either, the ac button has to be on or both of my switches are bad.

Wiring is correct so scratch that idea.

[nando]

no, it doesn't

but the thermoswitch in the radiator isn't designed to turn on until 90c for the low speed, and 100c for the high speed. There is also a resistor on the low speed circuit, so if it's bad the fan won't come on until your engine is really hot.

[jlevie]

My reading of the wiring schematics indicates that aux fan control runs through the unloader relay, which is only engaged when A/C is selected. So I'd say that the A/C has to be on for the radiator mounted thermoswitches to control the fan.

If you are going to retain AC you should retain the functionality of the existing system and control the electric fan (presumably replaces the engine driven fan) with a separate thermoswitch and relay. I think your car would have two thermoswitches in the radiator and you can replace the upper switch with a later production dual switch. Then install an 81-82C thermoswitch in the lower position and use it to control a relay for your fan. As noted above, the switches for the aux fan operate at too high a temp for routine engine cooling needs.

If you aren't going to retain the AC simply replace one thermoswitch with an 81-82C unit and wire in a relay for your fan.

[nando]

My reading of the wiring schematics indicates that aux fan control runs through the unloader relay, which is only engaged when A/C is selected. So I'd say that the A/C has to be on for the radiator mounted thermoswitches to control the fan.

If you are going to retain AC you should retain the functionality of the existing system and control the electric fan (presumably replaces the engine driven fan) with a separate thermoswitch and relay. I think your car would have two thermoswitches in the radiator and you can replace the upper switch with a later production dual switch. Then install an 81-82C thermoswitch in the lower position and use it to control a relay for your fan. As noted above, the switches for the aux fan operate at too high a temp for routine engine cooling needs.

If you aren't going to retain the AC simply replace one thermoswitch with an 81-82C unit and wire in a relay for your fan.

but it doesn't. All I have is the electric fan, stock wiring and relays, and lower temp thermo switch - no AC, never touched the switch. it comes on when the engine gets hot and shuts off after it cools down, just like it should. there's already a relay circuit there..

[328ijunkie]

I replaced my stock (pretty sure dead) temp switches with a 80C one which comes on right above the middle mark on the temp gauge. AC is never on.

[surebimmer]

http://www.understeer.com/fanclutchmod.shtml

That's what I run with no engine driven fan. Just stock Aux fan. Comes on at 80 C.