2015 GMC Sierra 1500 crew cab defrost door not opening

[Fowler17z]

I just bought a used 2015 GMC Sierra 1500 ale crew cab. 5.3 eco tech engine. My issue is that when I press the front defrost button it just blows through my vents. I’ve read that there is blend door reset by pulling out the fuse. I’ve tried that but with no luck. Maybe someone has better instructions for it or possible the directions to replace the actuator for modes of air flow. Thank you 

[SierraHD15]

I have similar problem except mine stuck on defrost. Returned to where I bought, they fixed but lasted a day, now same issue. I replaced the mode door actuator but didn't fix it. Tried resets still didnt fix it. Gonna ask around and I'll keep you posted if I figure this out. 2015 Sierra HD 6.0l

[Fowler17z]

Man sorry to hear your dealing with this problem also. I talked to the dealership I got it from. They said they’d fix it for free since it’s a safety hazard to have the window all fogged up. I’ll update you on what the actual fix is. Hopefully it last longer than one day. I’m about 100 miles from the dealership 

[SierraHD15]

2 hours ago, Fowler17z said:

Man sorry to hear your dealing with this problem also. I talked to the dealership I got it from. They said they’d fix it for free since it’s a safety hazard to have the window all fogged up. I’ll update you on what the actual fix is. Hopefully it last longer than one day. I’m about 100 miles from the dealership 

Noticed with mine after key on if I change mode it wont change. If i change mode turn off truck then restart it will change to the mode I selected. Sounds like electrical issue with control module  control head or BCM. I'll call dealer tomorrow and see what they say.

[Fowler17z]

So courtesy Chevrolet in Chico replaces the actuator assuring me this is what it was. Lol we’ll two fridays of appointments and alotta bs to deal with at that place. And the problem still persists. Btw that place is a nightmare to deal with. There very unorganized. To start with they mixed my truck up with another truck and sent my truck for an oil change at a oil change shop! WTH. That took 2.5 hours before I called and then they noticed my truck wasn’t there. When in fact it was supposed to be getting worked on and complete but nope it was at a different place getting an oil change I never even wanted to happen. It still had 89% oil life. And honestly I don’t trust quick oil change shops to touch my oil. But after that. They Install the part. Was only supposed to take another hour they tell me. And 2.5 hours later they confirm that this part that I paid for was not the problem. Awesome. Lol so I left and honestly don’t ever wanna deal with that company again. So now next Friday I have an appointment at another Chevy/gmc dealer and told them all about it. So I will update with those results. But I’m betting on the blend door being broken/stripped out. Word of the wise. Don’t go to Chico courtesy Chevrolet for anything. Unless you don’t mind  wasting alotta time and partially being lied to over and over again. Today was only supposed to take 1 hour in the shop. I got there at 830 and finally drove my truck away at 130 with nothing fixed. They are nice people. But In the end nice people aren’t exactly what I went there for.