1st of all I'M no mechanic expert so bare with me lol..
I have a 2000 Chevrolet Silverado 1500 Z71 EXT Cab truck, the other day I was heading to the Ranch and had the ac on, I was getting a lil cold so I moved the control to warm and it started blowing super hot air. When I tried to turn it back down to cold it would still blow super hot air, no matter what I did hot air was still coming through. I then had to pull over and pull the fuse so it wouldnt blow at all. Once I got to the deer lease I checked all fuses everything was ok, I then proceeded to pull the front dash cover off and I manually unplugged the AC/Heater Control and then replugged back in, all of a sudden it blew cold air again like normal. I then tested again with hot air and same thing hot air and would not blow cold again until I unplugged the AC/Heater control. I was assuming it was the control box that was bad since once I reset it all was fine, I then ordered a new control box and put the new one in today and you guessed it same thing... Can anyone help a computer geek out here...