Rear HVAC not blowing

[Orange]

2007 Cadillac Escalade. Everything was working fine until a few weeks ago when we had a battery drain. Battery replaced, and front HVAC blowing strong and cold, but rear has no air flowing.

What are the steps to diagnose which part went bad? I checked all the fuses under the hood and under the dash, but not sure how to check next. Could a solenoid have went bad? How I do check those?

All help appreciated.

 

[sk1dm4rk]

Are you pressing the AUX button on the HVAC panel? Once you do that, the rear controls should work.

The whole system is not very intuitive IMO.

I found this on another site:

Steps that work:
Turn off AUX. No light on.
Set temp on driver side that you would like the rear to be.
Press AUX. Now the rear is set.
Now you can change driver temp without changing the rear temp.

BUT

To adjust the rear temp, you must do the whole process over again until the kids can reach on their own...

 

[Orange]

Are you pressing the AUX button on the HVAC panel? Once you do that, the rear controls should work.

The whole system is not very intuitive IMO.

I found this on another site:

Steps that work:
Turn off AUX. No light on.
Set temp on driver side that you would like the rear to be.
Press AUX. Now the rear is set.
Now you can change driver temp without changing the rear temp.

BUT

To adjust the rear temp, you must do the whole process over again until the kids can reach on their own...

Yes, it's not the Aux button. No air blowing out the back no matter what setting it's set to. I checked all the fuses that had to do with HVAC operations (I think) none are blown. Could it be one of the larger "fuses" in the fuse block? How do I check? What's next on the checklist?

 

[sk1dm4rk]

Do you have access to a Tech 2? If so, you can use it to command the hvac to do whatever you want. That would help in narrowing it down. If not, post your general location and someone close to you may be able to help. If none of that works, it may be worth the diagnostic fee to take it to the dealer.

Good luck.