2003 Silverado AC Compressor will not engage

[John McGraw]

My 2003 Silverado will not engage the compressor. No voltage at the low pressure switch, no voltage at the fuse in the underhood fuse box. Anybody have a schematic of the system, so I can chase the circuit back? It is a manual system. Where does the 10 amp fuse in the underhood fuse box feed from?

 

 

Regards, John McGraw

[Dustoff87]

Does your defroster work? I had a silverado where the AC wouldnt work when set to cold but worked when the defroster turned in. If remember correctly it was a pinched wire in the dashboard.

 

[John McGraw]

Nope, does not run in any mode. I was told this morning that the 10 amp fuse that feeds the compressor clutch relay should be hot at al times, even key off. This would appear to be the problem, as the fuse terminals have no voltage to ground at any time. I will flip the fuse box upside down this weekend and see if I can identify where the connection has been lost.

 

 

 Regards, John McGraw