ima get one from ya too in a lil bit .. when i pay my tranny bills off, hehehe

 

so how does it work? One always on, and the other kicks on when the A/C is on ?

 

With the 2 relay harness, one fan comes on full speed with the PCM set point, the other comes on full speed with the A/C.
With the 3 relay (witch everyone seems to want) they both come on half speed with the PCM, if the temp is not met, and the A/C is on, one runs full speed, and with the temp met, and the A/C on, they both run full speed.

 

where does this or any other harness "tap" into the AC to know to turn on the fan when you have just started up a cold truck but want the air moving across the condensor that the AC actually cools off, I did this mod to my truck last summer and sweated myself silly every day for 5 min till the engine temp got up to the point where the computer turns the fan on and the ac actually starts to cool...???

Bueller?

 

I tap into the A/C wire that runs in the loom that goes behind teh red Batt box thats mounted by the alt.

 

I have the original prototype of his 3 relay setup on my truck, works great.

The wire for the a/c is the one that commands the a/c clutch to engage. I think it's the med. green one (get a multi-meter and test for yourself) in the harness pictured, just use a regular t-tap for the signal to the relay.