Hey guys, hoping someone can help me out here. Recently had an issue with my AC compressor not kicking on. Checked the shim, replaced it and measured air gap and that’s within spec. Evacuated refrigerant, vacuumed system, no leaks. Recharged it to spec. Replaced AC compressor relay but compressor still not kicking on. Tried to check power going into AC compressor and no power. So coming out the relay to compressor im not getting any 12v. I manually applied power going into the compressor and it starts working. Trying to understand this wiring diagram here. On pins 1, 2 and 3 im getting 12v but isnt pin 3 suppose to be a ground from the ECU? What could be giving that 12v? Any help is greatly appreciated!!

 

assuming you're talking about the pins on the A/C compressor relay:

Pin 3 will read high until the ECU sends ground.

 

Yes, thats what i meant. Sorry for the confusion. Do you happen to know what parameters have to be met for the ECU to send this ground signal?

 

Going out on a limb, have you spec'd out both the dual pressure switch and the radiator fan controller?