Howdy. I posted basically the same thread in the HD trucks section and only had one noteworthy response. So I am trying again, this time in the engine area. Sorry guys but the question is with the A/C. My 03 2500HD D/A A/C only blows cold sometimes. Additionally, I can not hear the compressor relay cycle anymore (it used to make a chirping type noise behind the dash). Has anyone else had this problem? Any ideas on what the problem is?

Thanks in advance,

T

Check the low pressure switch, they are notorious for failing. Unplug the connector and bridge across it. Clutch fan should kick over.

Or, get it to fail then tap on the low pressure switch. The compressor should come on.

GMCSID, do you work at Oakland Truck Center? Reason I ask is me and a couple other owners of DMax's in the East Bay are looking to for some knowledgable DMax mechanics should any of us need help. Thanks...

GMCSID, do you work at Oakland Truck Center? Reason I ask is me and a couple other owners of DMax's in the East Bay are looking to for some knowledgable DMax mechanics should any of us need help. Thanks...
Yes, I am at OTC. We have an awesome Dmax tech that works almost exclusively on them. Including me we have 3 fully trained diesel techs. I am also the trans tech and work on transmissions almost exclusively. Whatever kind of problem you have ,we got you covered.

Thanks GMCSID. I'll keep you in mind.

Thanks for the help guys. I will check the low pressure switch.

Have a good one,

T