This is my first post here. Ive been working on a 99 1500 ac system the power button on the control head lights up when pressed and I found the wire coming out and it is sending a signal of on.i have checked the low and high pressure switchs the work .checked fuses and the relay there ok. with my power probe i can actuate the clutch form the relay and the compressor clutch works. seems like a open wire through the fire wall to the relay does anyone how this system works or where to test next

 

Did you get this figured out?