Intermittent air ride Compressor Issue.

[PParamedic]

Hello,

Sorry if this has been beat to death, but I searched the forum and couldn't find an answer.

Compressor on my 2007 Denali was not turning on. I checked for 12v at the ALC relay and had power. Tried jumping across the appropriate terminals, Compressor still didn't come on. I assumed the compressor or one of the related components was shot, so I replaced the compressor package.

First 10 times I started it, it ran and purged at startup just fine. A couple days later, it doesn't come on at every startup, maybe 50% of the time. I pulled the compressor and inspected the wiring harness and didn't see any problems. Anyone have an idea? Do I need to re program at the dealer?

Thanks in advance.

 

[OHSIXX]

If your shocks have not lost enough air then it might not kick on. Did you try weighing the back down with either a trailer or some people in the backseats?
Mine used to kick on alot but that was because my rear shocks were leaking. After I replaced the rear shocks and compressor mine didnt turn on at every startup. If my truck sits for 4-5 days then it will kick on.

 

[PParamedic]

If your shocks have not lost enough air then it might not kick on. Did you try weighing the back down with either a trailer or some people in the backseats?
Mine used to kick on alot but that was because my rear shocks were leaking. After I replaced the rear shocks and compressor mine didnt turn on at every startup. If my truck sits for 4-5 days then it will kick on.

I replaced the shocks less than a year ago so I don't think there would be any leaks, however I was under the impression that it should be coming on every time I start the truck. Am I wrong ?