HVAC Vent controls

JIM2002

MEMBER
2002 GMC SONOMA
6 CYL
4WD
AUTOMATIC
102,000 MILES

I am having trouble with the Defrost/Feet/Vent/AC control. It is a 2002 GMC Sonoma with ZR5 Package. When I go to put the air to blow on my feet or defrost nothing happens. I can turn the switch over to the AC mode and it will start blowing cold air. It still comes out the 4 vents (face). It only blows out of the 4 vents that point at my face. It will switch to AC and the AC works fine but it still only comes out of the 4 vents on the dash by my face. I use to be able to hear it switch and I no longer even hear it trying to switch.
Any ideas as to what is wrong?

7 Replies

SERPENTRACER

MEMBER
34 POSTS

Hello,

There is a mode blend door actuator that sounds like it is not working correctly here is a guide to help you fix the problem.

https://www.2carpros.com/articles/replace-blend-door-motor

Please run down this guide and report back.

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Saturday, February 28th, 2009 AT 7:22 AM

WIBRACKENS

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0 POST

Thank you for this post I had this problem and had to replace the mode actuator cost me $64.00 all fixed I love this site.

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Tuesday, November 12th, 2019 AT 11:26 AM

SLV123

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1 POST
2001 GMC SONOMA
6 CYL
4WD
AUTOMATIC
36,000 MILES

I am getting all the heat through the top vents OR the defrost and it wont blow out on the floor! Can you help?

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Tuesday, November 12th, 2019 AT 11:27 AM (Merged)

ROBBIET

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8 POSTS

Sounds like you likely need to check your vacuum hoses for cracks and breaks. Can't tell u where they all are, but you'll have to poke around unless the dealer can give you a schematic printout of where they run.

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Tuesday, November 12th, 2019 AT 11:27 AM (Merged)

TROYLEBLANC