The vents on my 05 Silverado began blowing only hot air this morning. Even both slide temp switches are at the bottom (cool) it still blows hot air. All other blower controls work OK. I've checked fuses and all are good.
Any advice is greatly appreciated.
Alan

 

Any new noises? I know that the blend door actuator can be problematic but I think that only effects where the air is coming out.

 

The blend door actually controls the mixture of hot and cold air. This is probably your problem. The mode door actuator controls which vents are being used. This is another actuator and they work separately from each other.

 

There ya go. I wasn't sure if I was remembering right. Thanks for clarifying.