So I starting having this problems and did some research and realized it’s somewhat common on hummer 2 and gmc vehicles around the years 2003-2008, and saw some videos on YouTube and tricks to recalibrate the actuator . This was basically disconnecting some fuses and then letting the system reset, so I did it and it solved the hot air problem and started blowing cold air. However , now sometimes it seems like it’s just stuck making a rotating noise while the hummer drives . Anyone ever deal with this problem?