My 06 Sierra started blowing hot air on the passenger side, no matter what I have the temp set to.
I have tried going from Auto to manual, banging, etc with no luck.
It is the Dual Zone system

Any ideas?

Of course my warranty just ran out a few weeks ago!

My 06 Sierra started blowing hot air on the passenger side, no matter what I have the temp set to.
I have tried going from Auto to manual, banging, etc with no luck.
It is the Dual Zone system

Any ideas?

Of course my warranty just ran out a few weeks ago!

Write a letter CERTIFIED MAIL to the dealer about the problem, and also ask if there's a Tech Service Bulletin for the issue. KEEP a copy.

I think for the time bein', you're gonna' have to get a wrench-on the dash yourself, or pay someone to go fishin' for ya'.