No Heat

2005 GMC YUKON
50,000 MILES • V8 • AWD • AUTOMATIC
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PAT4752
  • MEMBER
  • 1 POST
Hi,

My 2005 Yukon is not blowing warm air when in the heat mode. It will blow exceptionally cold air when in the air conditioning mode. ANy ideas what to check first?
Oct 6, 2008 at 12:32 PM
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.
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RASMATAZ
  • CAR REPAIR CONTRIBUTOR
  • 75,992 POSTS
Try replacing the thermostat for a start-don't work you could be dealing with a malfunctioning air mix/blend/mode/ doors to include an actuator/vacuum problems.
Oct 10, 2008 at 4:11 PM
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MDE012001
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  • 1 POST
no matter what setting it is on it blows cold air when the heat is on. I think it is doing the same in summer with a/c on just harder to feel. Iwas told it was the air mixer controller but not sure where that is on this model. tried to locate it behind radio and lost all power to truck. so now i am thinking it is some kind of short maybe. any ideas or help will be greatly welcome!!!
Apr 29, 2019 at 7:57 PM (Merged)
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HMAC300
  • CAR REPAIR CONTRIBUTOR
  • 48,601 POSTS
check your actuators to see if they are getting power and working generic pic below and a guide to help walk you through the repair.

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


Check out the diagrams (Below). Please let us know what happens.
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Apr 29, 2019 at 7:57 PM (Merged)