bluezq8

iTrader: (6)

After getting my AC charged on my truck, I found that with my HI/LO pressure switches, I can only program the LOW speed fans to come on with the AC. I would like for the HIGH speed to come on instead, but the way the PCM works, I can't do that.

So I have been tossing an idea around in my head and I want to get some input in case I may be missing something important. My plan is for the LOW speed fan wire to control the HIGH speed fan simply by switching the two wires coming from the PCM. This way when the AC is turned on, I will get the high speed fans. I will then swap the coolant temp settings for which HIGH and LOW speeds come on in order to restore normal operation.

Does this sound like a feasible trick to get HIGH speed fans with AC on? Or am I missing any details that would prevent this?

Pacer Racer

iTrader: (6)

Why don't you just hook a relay on the compressor output of the PCM and wire it in parelell with the high speed fan relay

bluezq8

iTrader: (6)

Would that pose a problem when the compressor cycles, by turning the fans on and off each time it cycles? I guess I could use that same concept by using the AC command wire going to the PCM from the AC controls though.