Anybody familiar with htr/ac controls on 04 Z71? My temp controls stick and you have to spin the control up and down till it finally decides to adjust to the temp setting desired. Im just wondering if you have to replace the whole control box or if there is some smaller part that usually goes out and can be replaced. Anybody?

 

sounds like the "control box" but you may check your vacumme lines. if they are broken they it could cause issues with the blend doors

 

Sounds more like a blend door actuator sticking. That is what mine did before failing completely.