Blend door not working properly

Tiny
COSMOSTOP
  • MEMBER
  • 2000 GMC JIMMY
  • 4 CYL
  • 4WD
  • AUTOMATIC
  • 91,389 MILES
When I turn my mode switch from max, A/C, or bi-level to heater blend or defrost, air only comes out of the dash vents. It won't switch to defrost or the bottom vents. If the car is started with the switch in heater or defrost mode sometimes it will come on but as soon as I switch to air or max air, it won't switch back.
Sunday, August 2nd, 2009 AT 4:54 PM

1 Reply

Tiny
KASEKENNY
  • MECHANIC
  • 18,907 POSTS
The issue with this is the mode door actuator has failed or the vacuum line has come off.

Here is a guide that will help with this:

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

Basically we need to access the door and use a vacuum pump and connect to the line and see if the actuator changes position. If it does then you have a vacuum line or source of the vacuum is the issue.

If it does not then this actuator is the issue.

Please run through this info below and let us know if you have other questions. Thanks
Images (Click to make bigger)
Thumb
Thumb
Thumb
Thumb
Thumb
Was this
answer
helpful?
Yes
No
Monday, September 13th, 2021 AT 2:57 PM

Please login or register to post a reply.

Related Blend Door Actuator Not Working Content

VIEW MORE