i placed a post about this earlier. i was told to clean the microswitch. i did and the air and heat was working. then i closed the door came back and nothing. i dont have anything at all. i took it apart again and all i hear is a click at the junction where the wiring harness from the heater control unit,plugs into the main wiring harness. it sounds like a relay click. my dilema is before i buy a new control unit, what else can i check? do i just start replacing relays or what? thanks guys for the help, michael