HVAC issues none of blend door motors Move all new?

Tiny
DUSTINISTRE
  • MEMBER
  • 2007 GMC SIERRA
  • 4.8L
  • V8
  • 4WD
  • AUTOMATIC
  • 15,700 MILES
2007 GMC 1500 4x4 classic dual climate control auto none of the 4 motor that control air are working iv replaced all 4 motors and controller. Controller comes on and can adjust fan speed and turn on and off compressor but will not go hot to cold or outside air to recirculate or from vent to defrost to floor.
Sunday, March 23rd, 2025 AT 5:17 AM

1 Reply

Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 50,271 POSTS
Hello,

I would check the HVAC BATT fuse in the fuse panel under the hood for power when the key is on. Also, there is a main ground (G200) for the controller which I would look at as well which is located at the right front corner of the HVAC module. Here are the wiring diagrams for the HVAC system so you can see how the system works. You can test the ground by unplugging the HVAC controller and this guide:

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

Check out the images (below). Let us know how it goes.

Images (Click to make bigger)
Thumb
Thumb
Thumb
Thumb
Thumb
Thumb
Was this
answer
helpful?
Yes
No
Sunday, March 23rd, 2025 AT 10:51 AM

Please login or register to post a reply.

Related Blend Door Actuator Replace/Remove Content

Blend Door Actuator Replacement
GUIDE
Blend Door Actuator Replacement
Do you hear a tick­ing noise com­ing from in­side your dash­board when the HVAC sys­tem is on? Does your car heater blow cold, or the air con­di­tioner blow hot? These are signs...
VIEW MORE