Thanks for the input PHAT. When you turn on the A/C (pressing the button that is) do you hear the compressor engage? It's very noticeable at idle as a click/thunk, which is the compressor clutch engaging. On my vehicle that only occurs when the fan is turned on or off.

If you know which pulley to look at you can also check if the compressor is running visually. That stopped the dealer really quick from telling me that click noise was just the fan turning on.

Kurt