Hello all. I bought an 05 Yukon SLT 5.3. Trying to get the ac working. New compressor. Trying to charg,however after jumping the low side switch, the compressor does not come on. Yes, everything is on high in the truck. The relay has power on pin 30. But the relay is not clicking. U swapped it out and it us a good relay. Not knowing what actually bumps the relay to engauge the compressor i put another control switch in the dash and that didnt work. I did jump power to the compressor real quick and it worked. Can someone guve me some insight as to why the relay is not switching over?
A/C compressor no power.
- Thread starter Brian7743
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You can find wiring diagrams on www.charm.li.
The important thing to know is that the system is computer controlled. All the various switches and such like the low pressure cycle switch do not actually turn anything on or off, they are just inputs to the controllers.
Air Temperature Part 2 — 2005 GMC Yukon/Denali 2WD V8-5.3L VIN T Service Manual | Operation CHARM
Detailed repair manual for the 2005 GMC Yukon/Denali 2WD V8-5.3L VIN T.
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Possibly blew a fuse when u jumped it? Low side switch has 3 wires or 2? I don't remember. Get a power probe or jump the ac relay. There should be a constant 12v on one and a switch on 12v at the relay. If u can't make the clutch click on and off from the relay then it's after the relay. Ur issue. But if u can u can work backwards and trace down the issue. Scanners help but I grew up with out them. Fallow the line.
