2004 Silverado A/C - Bad Switch or Low Freon?

[LBJ]

Thanks Hatzie, good information. I need to go get some R134a adapters for my old gauges.

Had a friend look at the clutch while I engaged it from inside the cab. He said it was engaging and wasn't making any noises. But, the little yellow light on the A/C power pushbutton would go off as soon as I pushed it, which it never does when working correctly. It finally came on and stayed on, but no cool air.

I'll look thru those service manuals to see where the 2004 hi and low pressure connections are.