AC/Heater stuck on defrost?

2008 CHEVROLET EXPRESS
27,000 MILES • 6.0L • V8 • 2WD • AUTOMATIC
Avatar
DAVID FOWLES
  • MEMBER
  • 1 POST
Temperature blows correctly, but air stuck on defroster.
Nov 4, 2022 at 5:40 AM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.
Advertisement
Avatar
STRAILER
  • AUTOMOTIVE REPAIR CONTRIBUTOR
  • 54,178 POSTS
This happens when the HVAC system loses the vacuum supply to the system. Check under the hood and looks for a small vacuum line that heads into the cab this will be the line that is broken. here is a guide that shows what I am talking about, and I have included the defrost actuator so you can check that out as well.

https://www.2carpros.com/articles/air-vents-stay-in-the-defrost-position


Check out the images (below). Let us know what happens and please upload pictures or videos of the problem.
Image (Click to enlarge)
Attached Media
Nov 4, 2022 at 12:23 PM
Advertisement