Ac Troubleshooting

[bmx_02]

Ill try be detailed but brief, I turn my AC on but i get nothin this is what ive toubleshooted but im stumped.

Its an 02 silverado LS with just the standard HVAC and AC button, non of that duel zone or auto climate stuff or rear auxillary controls.

 

Jumped the compressor at relay - Compressor engadged and the ac pipes got cold, so compressor is not the issue

Checked the refigerent charge - OK

 

so the problem is the circuit that triggers the relay, for the compressor.

 

Tested the relay and check all fuses - All OK!

Jumped low pressure switch - still got no compressor engadging

tested the ground and voltage to the low pres switch harness - had ground continuity and voltage, so its OK

tested the ground and voltage to high pres switch harness - had ground continuity and voltage to so its OK

AC light on HVAC control lights up when pushed and all nessessary settings are correct - OK

When turning AC system on, the truck slightly increases ide - Therefore the PCM is receiving signal from the HVAC control that AC is on.

 

Anymore hints or suggestions on what it could be or anymore tests that i should try?

[bill190]

Well you get an "A+" for troubleshooting ability!

 

Very good!

 

About the only thing left (sorry to say this) is I think there is a relay in the PCM.

 

To test that, I suppose you would need to take it to a GM dealer and have them hook up their computer gizmo, then see if that relay is activating or not.