A/C Cycles on (Even with A/C switch off)

My 98 Silverado (5.7L) A/C cycles on even when the A/C switch is turned off. At idle, I will hear it "click" on and the "click" off. If I turn the heater switch all the way to "high", that seems to keep the compressor from coming on. I am thinking a bad A/C switch or possibly a relay.

what are the chances that you have the selector on defrost ? If so they do that ,designed that way

The chances are pretty good that is the case! Thanks, I move the selector off of defrost and see what happens. I never would have thought of that. Any idea why that is the design?

It looks like that was the problem (or actually no problem). Thanks for the advice!

The chances are pretty good that is the case! Thanks, I move the selector off of defrost and see what happens. I never would have thought of that. Any idea why that is the design?

The design is, and it's been that way for a long time, that dehumidified air (from the A/C) will defog the windows faster. And it actually works!!!

Sure glad you posted back 'cause I was deep into wires, relays, switches, etc.

Good job "muff34".

I thought that if the compressor kept kicking on and off it meant the system was low? No?