I have a 1997 Yukon 2wd. Air conditioner was working then one day I pushed the switch on the dash and heard a small pop, light on dash does not come on now and no air conditioner. Recirculate light (switch) does not function anymore either and it does not appear that the flow adjuctment knob is working either. The fan switch does work fine. I checked the underhood fuse relay box and did not find any issues. I also checked the furse convenience panal and found no blown fuses. I swapped the compressor relay but no change. So I am thinking that there is another relay and/or circuit under the dash somewhere? Any suggestions on where to start tracing this out? I do have a good multimeter.