GMC Repair: Air stuck on defrost of 2004 Sierra 2500 HD, gmc sierra, gmc sierra 2500hd

Question
I have a 2004 GMC Sierra 2500HD with a 6.0 engine. I unhooked the battery to put a new starter in and when I hooked everyhting back up the truck would only blow out the defrost. I would like to know if there is anything to do to get it back to normal.

Answer
Hi
Try this actuator recalibration procedure......
Remove the HVAC/ECAS fuse for a minimum of 10 seconds.
Install the HVAC/ECAS fuse.
Start the vehicle.
Wait 40 seconds for the HVAC control module to self-calibrate

Try this..... it SHOULD work
Good Luck
Pawl