Bought my Tahoe late last year and everything has been working fine until just a few weeks back, it seems no matter what i do i cant get the rear heat to blow hot.... it stay freezing *** cold. if i didnt have my daughter i wouldnt worry about this issue but i would like to have it warm back there for her this winter.

Anyone have this issue? know how to fix?

 

Sounds like the Rear Temprature Door Actuator. Part # 89018375

 

ok, thats a lead, is there a way to diagnose? and where is it located?

 

Now that's service right there!

I had the opposite problem with mine (only ambient air, no A/C), turns out some junk was clogging one of the hoses and had to be flushed out. Hope it works out for you.

 

LOL....thank you sir! We see several problems out of the rear ac and climate control in the Tahoe/Yukons and Suburbans.

 

You can check the voltage across the actuator upon operation to see if it's working or not. Sometimes they just don't open all the way and hang up in the middle.

It's kinda hard to describe where the thing is. It is located on the rear section of the rear Aux AC Module in the left side inner quater panel trim panle. There are 2 identical actuators.

If you have a fax machine, I can fax you the picture.

 

I had to replace the Aux AC Module in mine. I had an AC shop scan the BCM to figure this out. FYI

 

thanks all for the help, ill make an attempt this weekend to dig in and see whats going on in there.... hopefully it wont be too cold....