I think there are several AC configurations, depending on which trim level you get.
My Laramie has a snowflake button that lights up when pressed and turns the compressor on and off.
Adjacent to it is the recirculation button whick also lights up when pressed. I believe this performs the same function as the "MAX" button on some systems.
My problem is that the button is stuck in the illuminated position. When I press it the light stays on and won't go off. The system is working, but remains in the recirculation mode.
I'll try removing the fuse, but since the light is on and the fan is running, it doesn't seem a likely source.
Will keep you posted.