question for you mechanics out there

[txfirefighter_04]

i have a 2005 gmc sierra and the passenger side air is blowing cold but the driver side and rear ac are blowing hot,any ideas??

[bowmech]

Bad heater control valve possibly, have it scaned by a guy that knows what he is doing.

[mikep453]

Your blend door motor/actuator is faulty. It's more than likely stuck causing the heat to blow on one side. Not an expensive fix nor difficult fix. Just a little time consuming (about a couple hours) depending on your vehicle. There is one for the driver side and passenger side. I heard one of them is a bit more of a pain than the other but I can't remember which one.

[Texasredneck]

Bad heater control valve possibly, have it scaned by a guy that knows what he is doing.

x2