Hi everyone:

I just wanted to share a little project that I did this weekend. I added a switch to make the electric fan kick on that is in front of the radiator when idling with the A/C on. It does not automatically come on when the A/C is on in my '91 - only when the coolant hits a preset temperature (and possibly when the A/C high pressure side gets too high.)

I used an off-the-shelf rocker switch from Auto Zone, some 18 gauge wire (sufficient gauge as the load is low - only energizing the fan relay in this application) and some crimp-on bayonet connectors to make a "bridge" to kick the fan on with my switch. The factory relay for the fan is next to the Radio supression relay on the passenger side strut tower under the hood. I did not hack the original wiring in case I want to put it back to "stock." I made a couple of pigtails for the each side of the stock radiator fan switch, cut a hole in an empty blank-off plate in the dash and added the switch. The original wires are connected to the sensor as well.

Now when idling I flip the switch on and the e-fan keeps more air moving through the condenser. The A/C is a bit cooler at idle and I can exercise the e-fan as well. When moving, I flip the switch off as the e-fan just gets in the way at higher speeds. When the switch is off, the factory radiador temp switch will still kick the fan on if need be.

Regards,

Andrew S.

'91 744 B230F 170K