HELP!!! A/C is blowing through Defrost vents 98% of the time

[nmanzie]

So, I changed my battery about 6 months ago. And I went through all the reset/recycle steps I've seen but my a/c is still blowing through the defrost vents. Every once in a blue moon it may go to the face vents, but then after a minute or two, you can hear the door close and only blows through the defrost vents. I'd like to fix it, but I only want to replace the actual actuator that is doing this. Would you have the part number and installation tips?

 

Also, on separate note, my rear a/c has completely stopped working. Nothing. no air at all. Any thoughts?

 

Thank you for your help. I have a 2006 GMC Yukon XL 1500 - SLT Trim - 5.3L V8 - Flex - Automatic Controls

Edited September 14, 2020 by nmanzie

[Brandie Smith]

had similar issue with my 96 gmc 1500, had it checked by local shop they couldn't figure it out so i got down and dirty got down under the dash board and found that the seal had become so sticky it would catch and stop the actuator from working, clean up the sticky seal around it and now works like new with 0 issues.