Did you remove the HVAC B fuse in the rear fuse box to start the recalibration process?

Assuming the recalibration process was properly done (correct sequences) then more than likely one of the actuators is faulty. When a faulty actuator is identified in the recalibration process the process stalls where it is and the remaining actuators will not recalibrate.  The mode actuator is by far the most common actuator to fail on your vehicle and it is relatively inexpensive and moderately easy to change. To be properly diagnosed the HVAC codes and data stream need to be checked with an appropriate scan tool.

I am assuming that the battery was disconnected to repair the blower issue. When it was reconnected the recalibration procedure was automatically started. That is why we professional mechanics who deal with this stuff all the time rarely disconnect a battery anymore while performing repairs. You may also have a low idle/stalling problem now because of the battery disconnect and the throttle body carbon build up will need to be “Properly Removed” to correct that condition.

Well that makes things interesting. Let’s confirm you have the correct recalibration process.

• Nothing connected to the DLC under the driver’s side of the dash.
• Remove the HVAC B fuse for at least one full minute.
• Re install the removed fuse.
• Start the engine.
• Do Not Touch Anything, hands in pockets.
• The displayed set temperature on the HVAC control panel should default to 74 indicating the process has started. May only stay there for a few seconds until turning back to outside temp display.
• Allow the engine to run for at least one full minute.
• Turn the ignition off for at least ten seconds but no longer than thirty seconds.
• Restart the engine and check HVAC operation.

If the system does not recalibrate properly after several times of trying the above we will have to assume you have a faulty actuator  but I would recommend having codes and data read as mentioned earlier .

It won’t hurt to try but most likely one of the actuators has failed and locked the system. There are a total of five actuators and it is difficult to determine which one or ones have failed without an appropriate scan tool.

Oddly enough once in a while if you just leave the vehicle alone overnight it may correct itself in the morning.

These article should help.

https://sparkys-answers.com/2009/05/2003-gmc-envoy-no-ac-vent-control-b0263.html

https://sparkys-answers.com/2010/12/2004-chevrolet-trailblazer-identifying.html

There is also the fresh air/recirculation actuator that is located behind the glove box area.

I wish I could say that helps but sadly it does not. My experience tells me that the faulty actuator will likely be the mode actuator or the defrost actuator. However nothing beats knowing with codes and data. The only other way to get some sort of insight into which actuator may be failing is to have some one else perform the recalibration while you physically look at the actuators and see which one may try to move but will not move the full 90 degree arc. It may take  quite a few tries to figure anything out. It may also waste a bunch of time and put a crick in your neck.

It shouldn’t be causing a problem but I rarely say never about odd electrical problems. If you happen to have the original part you could reinstall it and recalibrate one more time to see if the problem goes away. I would however recommend using ACDelco replacement parts for your vehicle electronics  whenever possible.