I have deleted the AC on the 89 Turbo and was thinking of using the AC "snowflake" switch to turn the cooling fans on high speed...kind of like an over-ride. Currently the fans come on with the switch but only on low speed until the 102 degree part of the coolant temperature switch kicks in. Is there a way to accomplish this without too much difficulty? I thought this would be a good mod on these hot track days to keep the motor cooler and still maintain the automatic fan operation.

 

Interesting idea - I imagine you could rig up SPST contacts behind the snowflake button or simply jumper onto the existing connections if you wanted. . . I've taken that center climate control unit apart and it is not a job for the faint of heart - the clear plastic loves to shatter and there are little pieces galore to lose. Maybe simply running the circuit directly off the existing wiring to the a/c clutch?

 

This is easy to do. I wired mine for manual operation both on low speed and hi.

Tap into the temp sensor at the radiator (lower driver side of rad). On my TurboS, the red with a white stripe is the 102 degree leg, and the brown with the yellow stripe is the 92 degree leg. I cut through the back of the rubber weatherproofing and looped the end of the wire over the spade connector. Then run the wires up through the engine bay and somewhere through the firewall.

Run these wires through any switch to GROUND.. The fan relays are not powered through the temp switch, but rather grounded.

I had removed my foglights to duct air into my oil cooler so had no use for the foglight switch. I bought an extra switch from George B. and placed it where the Euro driving light blank is located. I can now turn the fans on hi speed when I exit the track and keep the low speed running when the car is parked and engine off.

The low speed will run anytime, so don't forget and run your battery down. The hi-speed will only operate when the key is in the accessory position.

 

Thanks for the ideas guys. I have the schematics and been trying to figure out the best way to do this. I liked the idea of using the AC switch that is lighted and no longer used and is linked with the ignition switch. I guess I could use the 12 V off the compressor feed to fire a solenoid relay which will then use the switch part of the realy to complete the ground path for the 102 degree feed. This should still allow the fans to run on low after the car is turned off.

 

I run wires directly to the fans back to two switches on my 944-spec car.

Works great, but is not quite elegant.

 

I too placed a toggle switch under my stereo in a gauge panel, however, I tapped into the fan relay, in the fuse box. I could tell you which prongs I put it on. It was trile and error after examining internal circuit of the relay. btw i have one switch for high speed

 

Thought I would post my final results so those who want a mod like this will know the end result ;^)
What I ended up doing was this...usinga a fog light relay that I had laying around, I made a barrel connector to attach to the black/red stripe wire that used to hook to the hi/low pressure switch on the AC. this is the main 12v feed coming in and will later feed the AC clutch. I ran that to the solenoid tap on the relay and the other side of the relay to ground (which is right there for the headlights). This effectively energizes the relay when the snowflake button is pushed in the cabin. From there I soldered a wire to the red/white stripe wire on the fan temperature switch (located on the radiator and the red/white wire is the 102 degree ground path) and ran it to the common tap on the fog light relay and jumped the N.O. side of the switch to ground already ran for the solenoid. Attached the relay to one of the studs on the fender where the AC condenser? used to be. Works great! And I only had to run about a foot of wire. When I want high speed fan operation I just push the snowflake button. The great thing is it will go back to low speed/ automatic operation when the key is switched off so I don't have to worry about draining the battery. Easy mod and can be done for less than 5 bucks.