2021 Tahoe A/C blowing warm on driver side.

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DanJanson

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Having an issue with my 2021 Tahoe where the A/C blows warm in the driver side front only. Passenger side front and rear are good and cold. First thought for me was this must be a blend door issue. The blend door does work at least partially because it goes to from warm to hot but never cold. I’m a heavy duty diesel technician and have plenty of experience with blend door issues and thought I’d try and figure this out before it gets too hot here in Texas. I removed enough of the dash to get to where I could see both the passenger and driver side blend doors actuators. I removed the driver side actuator and used my hand to turn the blend door in both directions but still going from hot to warm. Did the same on the passenger side and it goes hot to cold. Scratching me head at this point. The only thing I can come up with is that maybe the blend door itself is broken or something is in the way of it being able to close all the way. Really just looking for more information on how the automatic climate control works. I used Snapon scanner from work to recalibrate the blend doors but there is no change. Are there separate blend doors for hot and cold? Any help is appreciated.
 

Joseph Garcia

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Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please.

@swathdiver may be able to provide you with some perspective on the blend door system and troubleshooting procedures.
 

Doubeleive

Wes
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Having an issue with my 2021 Tahoe where the A/C blows warm in the driver side front only. Passenger side front and rear are good and cold. First thought for me was this must be a blend door issue. The blend door does work at least partially because it goes to from warm to hot but never cold. I’m a heavy duty diesel technician and have plenty of experience with blend door issues and thought I’d try and figure this out before it gets too hot here in Texas. I removed enough of the dash to get to where I could see both the passenger and driver side blend doors actuators. I removed the driver side actuator and used my hand to turn the blend door in both directions but still going from hot to warm. Did the same on the passenger side and it goes hot to cold. Scratching me head at this point. The only thing I can come up with is that maybe the blend door itself is broken or something is in the way of it being able to close all the way. Really just looking for more information on how the automatic climate control works. I used Snapon scanner from work to recalibrate the blend doors but there is no change. Are there separate blend doors for hot and cold? Any help is appreciated.
stick a camera up there and check it out, manually moving the door should make it work 100%
 
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