Looking at how The Manuals describe my ‘11 - and this is assuming “Manual” HVAC system, you have at least three components here: the (1) Radio/HVAC Control panel which accepts the button presses to direct the air, the (2) HVAC Control Module, which gets the button presses from the Radio/HVAC Control to Control a (3) Mode Cam Actuator, located under the left-side dash below the steering wheel.
So now the question(s) are:
1.) Are the button presses at #1 getting to #2?
2.) Is #2 commanding #3?
3.) Is #3 getting the command, and if so - is it malfunctioning (or just dead)?
Without the aid of a professional scan tool to check #1, #2, or the network between them, I would just go straight to #3 by removing the small panel below the steering wheel and then removing the (3) screws holding the actuator in place - because that’s the most likely point of failure.
Can you hear any noise at this actuator when you press the buttons on the Radio/HVAC panel? I *twice* had something similar fail on my ‘97 Taurus when the same internal plastic gear cracked a tooth! In each case, you could hear it turning (and trying to move the air “blend” door), but when it reached the cracked tooth the door would fall down.
If you can’t hear anything, maybe you only have a blown fuse, but in 30+ years of maintaining all my vehicles - I’ve yet to replace a single fuse...
2011 Equinox 1LT (new Jan 2011): Summit White / 3.0 L V6 / FWD / Pioneer Stereo / 18" Wheels / 138.2k miles [05-NOV-2019]
2002 Impala 1LT (new Jun 2002): Summit White / 3.4 L V6 / FWD / Cassette-CD Combo /225.5k miles [05-NOV-2019]
Last edited by Colt Hero; 06-22-2019 at 05:04 PM.