a/c problem on 1999 GMC Sierra 1500

the clutch on my a/c clicks off intermittently when I turn on the a/c. It will not run long enought for the compressor to come on. What is the problem?

1 answer
You may have a faulty pressure cycling switch, located on the a/c accumulator of your 1999 GMC Sierra 1500. If you tap lightly on the pressure switch with a screwdriver handle and the compressor turns on, replace the switch.