Hey everyone, I was driving my H3 Hummer 2006 last night when I felt the AC kept switching to the feet vents and off the face one. I kept hearing the whirring of the vents switching and did not think much of it as my car has done this before. It began to quicken the rate at which it was switching vents and then I realized my recirculate button was also turning on and off as this happened. When the recirculate button would turn off it would switch vents to the floor. I replaced all my AC actuators about a year ago with ones from the dealership (which was not a fun task to do). I’m not sure what is causing the connection between the recirculate and the vent switching? I have attached the video of what was happening, I eventually turned my AC off but it continued switching like this. Any advice would be helpful as I just spent a lot of money getting my camshaft sensors and throttle body replaced.

 

Weird. I wouldn't think that light would turn on if the fan is off, but I'd have to check the behaviour.

Disconnect your batter, tie the cables together for 30 minutes.

Maybe a computer thing.

 

Pull the HVAC control module, take apart and inspect for fluid intrusion/corrosion, then clean with CRC QD Electronic Cleaner replace the bulbs while you're in there:

 

There was a recall from GM years ago on the fan switch. Could this be related somehow?

On my 06 h3, this happend 17 years ago.