I have a 2007 2500HD Silverado Lt. 6.0 gas engine. I just acquired this truck a couple weeks ago and slowly been trying to get everything working good. I had a manual dual Climate control module that had nothing working on it except for the highest speed fan. I replace the fan motor resistor and now have all speeds working. None of the other controls on the module are working. The rear defrost, a/c and recirculator don’t work. No button lights also. I replaced the module and still nothing. I did replace the blender actuator also and that isn’t working also. I tried the re-calibration procedure that you recommended and no actuators move.
Because of the year model I need to know if your Silverado is the Classic or New body style?
Classic body style
It seems like the climate control module isn’t speaking to the actuators. Actually…. seems like it isn’t speaking to anything
Check the HVAC 1 fuse in the driver’s side interior fuse box. Make sure it is both good and it has ignition power with the key on. If the fuse is good and there is ignition power there then the next step would be to check for power at the brown wire, B5 of the C1 connector at the rear of the HVAC control panel.
Fuse is good and power is there. I’m taking that the C1 connector is the black connector and there is 12V there.
Someone had suggested that it could be a bad “BCM”. How could I test that?
The BCM has no interaction to the HVAC control panel in relation to the actuator functions or the LED’s lighting up on the push buttons. I would recommend checking the ground for the control panel and reconfirm power is good to the control panel. I am including a diagram attachment to assist in wire/circuit locations. If power and ground are okay I would suspect either a poor terminal fit at the control panel harness or a faulty control panel. I also recommend checking the powers and ground under load. I also use a headlight bulb to load the circuit. You would need to rig up a harness and backprobe terminals so you do not damage the vehicle harness.