I just did a motor swap in a lightning that I bought. Truck had no engine so I do not know the history of what did and didn't work. The motor I swapped in is built and I used the ac compressor from the donor truck, which worked fine. Here's the problem, had ac filled up to factory specs, ac blows ice cold like it should. With the fan control set to OFF, the compressor still runs... Doesn't matter what position it's in, it runs. I swapped the hvac control unit with my other truck thinking I had a bad switch. No fix. I checked the compressor relay, it's good. Fuse is good. I pulled all the relays, fuses and the diode, still spins! Unplugged both pressure sensors, still spins! Unplugged the compressor plug, it doesn't spin.... Whats goin on here? How can it be engaged with all the relays fuses and pressure sensors unplugged? Any help would be greatly appreciated.
