[SOLVED] Weird HVAC issue after battery replacement

[cooki3mnster]

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]

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]

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]

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......

 

[cooki3mnster]

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

 

[swathdiver]

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.

Who do you know with a Tech-2 or equivalent?

 

[cooki3mnster]

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]

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.

Tech 2 Owners Map

There are quite a few members that have a Tech 2 and there are always people who wish they had one to use so I thought I would post this thread to try and help each other out. If you own a Tech 2 and would be willing to help out another forum member that might be local to you then post up your...

www.tahoeyukonforum.com

 

[cooki3mnster]

Where are you located? We have a few members spread over the US.

Tech 2 Owners Map

There are quite a few members that have a Tech 2 and there are always people who wish they had one to use so I thought I would post this thread to try and help each other out. If you own a Tech 2 and would be willing to help out another forum member that might be local to you then post up your...

www.tahoeyukonforum.com

NorCal - about 50 miles east of SF in Livermore.

 

[Doubeleive]

I'm in stockton but the tech2 won't really do more as far as calibration then unhooking the battery but if you want to test the actuators take a drive over the hill

 

[cooki3mnster]

I'm in stockton but the tech2 won't really do more as far as calibration then unhooking the battery but if you want to test the actuators take a drive over the hill

Awesome thanks for the offer. I'm going to try the above steps and report back. I have the next two weeks off so I have plenty of time take the dash apart and swap in some new actuators and clean everything up.

 

[cooki3mnster]

Well after some troubleshooting it turns out the drivers side actuator was the culprit. I decided to replace both the actuators and all is well.

The whole process from start to finish took me about 2.5 hours including two trips to the parts store one for an actuator and a 5.5mm socket, and the other for a new ambient light sensor since mine disintegrated in my hand on removal. The actuator for the pass side wasn’t too bad once you loosen the 2 10mm bolts on the pass side of the dash and pull it away from the mount. You’re then able to prop the vent register up on top of the dash cover and can actually get a hand in there to get at both screws and remove the actuator.

The drivers side one was much easier and just required removal of the kick panel on the pass side foot well and it’s right there. I tested the one that cam out and it would self test and then get stuck in place and. Or move no matter what temp I dialed in on the dash. It looks like the drivers one had been replaced at some point once before as it didn’t match the pass side one under the dash.

Thanks everyone for the advice and input!