Hello, I have a 09 Suburban 1500 LTZ. I am having problems with the a/c. It blows cold air on drivers side, heat on passenger side and rear vents. When you select the air vents on dash it blows for a few seconds then changes to defroster vent and show dash vents on display. If you reselect the dash vents it will change back to dash vents and then return back to defrosters. When I turn off the climate controls I can hear a clicking sound on the drivers side under the dash. I have reset the system by pulling the HVAC fuse, but didn't make any difference. Thanks for any advice!

Just that clicking sound by itself makes me think of the door actuators on the HVAC Module.

Here'* a pic of an '09 2WD Frt Module: You've got 2 # 4 Actuators; a # 10 Actuator; and a # 26 Actuator - indicated with red arrows.

Good possibility you have a bad actuator/*. Gain access to the actuators and watch them while operating the modes on the controller. The gears inside the actuators like to strip, and the position sensor inside also like to go bad, causing the actuators to sometimes hunt for a position.

Thanks for the info! I currently unplugged the actuators for ac! I think I am going to replace them!