Okay I've got an idea here and I'm wondering if it will work....
I have a '99 Civic Si and so right now my radiator fan is hooked up to the thermoswitch which is then hooked up to IGN2. My turbo timer is hooked up to IGN1 So when I turn off the ignition and the turbo timer keeps the car on, the radiator fan turns off (or will not turn on).

Is it possible to wire the thermoswitch (ECT) up to straight +12V? I was thinknig this way the fan could turn on regardless of whether the engine is on or off or whether the key is on or off, and would be purely temperature dependent.
If i remember correctly, my mom's old subaru was like this -- on hot days the fan would stay on for a little while even after taking the keys out and turning off the car.

I've been looking through my helms manual and I think I know where in the signal path i need to change the wiring, but i don't know where it's physically located in the car. Has anyone else rewired their fans to run off a different signal than IGN2? I would still like to use the thermoswitch to turn the fan on and off.

Actually, while we're on this topic, I know that some of you wired in a switch that will force the fan on when turned on, or allow the fan to run off of the thermoswitch when off. Any tips on how to do this?

thanks
-Xerxes

 

TTT! any thoughts?

 

okay one more try. does anyone else have their radiator fan hooked up differently from stock? please read!

 

I used to have my fan wired to a 12v ignition source so it would always come on when the car was running. However, my car never overheats so I have it back to stock. Hope that helps.

Oh and you can use a meter to test for a 12v ignition signal, there is a wire by the harness to the fan I tapped off of.

 

my fan comes on when the ignition is off. Its anoying because it sets off my alarm.

 

Yeah, mine come on with the turbo timer counting down.. it sets of the shock sensor on my alarm.

 

Sounds like a good idea. Let me know if it works. Oh ya, I also had my fan running straight to the fuse box so it always ran when the car was on. I like your idea better.