[SOLVED] Weird HVAC issue after battery replacement

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cooki3mnster

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I recently had to replace my washer fluid bottle and battery. After I replaced the battery my wife drove the truck to work. When she got home the Drivers side vents were blowing hot air and the pass was blowing cold. After a quick search I tried this recalibration method:

  1. Clear all DTCs.
  2. Place the ignition switch to the OFF position.
  3. Install the HVAC actuator.
  4. Connect all previously disconnected components.
  5. Remove the HVAC/ECAS fuse for a minimum of 10 seconds.
  6. Install the HVAC/ECAS fuse.
  7. Start the vehicle.
  8. Wait 40 seconds for the HVAC control module to self-calibrate.
  9. Verify that no DTCs have set as current DTCs.

Now the drivers side blows cold air and the pass side blows hot. When pressing the mode button it will change from dash vents to defrost, to footwell but I cant get the temp to change. I've already called the local parts house and ordered some actuators. Is there anything I can check before I start taking the dash apart to replace them? I feel like if the actuators had failed they wouldn't have moved after the calibration. Or maybe I'm over thinking.

EDIT: This is a 2005 Yukon XL with digital controls and Rear Aux A/C.
 

Trey Hardy

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You can try taking both battery terminals and holding them together while there disconnected from the battery to reset all the systems along with the fuse under the hood and run it through the calibration steps for the hvac temp door actuators
 

Trey Hardy

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My Tahoe anytime it goes dead or you disconnect the battery it does the same thing one side is cold one side is hot usually the driver side is hot and sometimes the rear vents will blow hot oddly I drive it some and it usually fixes its self once I park and restart the car but mines a 07
 

Doubeleive

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unhook the battery ground, hook it back up, turn the key to run (not start) let it sit 30 seconds or so (time to let it self-calibrate) then start it up and see if it goes back to normal.
when you do this you should be able to hear the actuators moving around if you listen carefully, some people are not tuned into there vehicles......
 
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cooki3mnster

cooki3mnster

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Thanks for the input guys, I'll give it a try tonight and see what happens.
 
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cooki3mnster

cooki3mnster

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Who do you know with a Tech-2 or equivalent?
The only person I know that would have one moved to New Zealand earlier this year. I've been thinking about pulling the trigger on one and this might be the push I need. chinacardiags has one listed for $269 right now
 

George B

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The only person I know that would have one moved to New Zealand earlier this year. I've been thinking about pulling the trigger on one and this might be the push I need. chinacardiags has one listed for $269 right now
Where are you located? We have a few members spread over the US.
 
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cooki3mnster

cooki3mnster

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Where are you located? We have a few members spread over the US.
NorCal - about 50 miles east of SF in Livermore.
 

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