Rhaunschild1980

still blows hot air from rear vents. Holy crap! It worked for about 15 minutes then started blasting hot air from the rear. Any thoughts or suggestions on my next move? I searched all over and have found no resolution or next step! Thanks in advance for your time.

Rhaunschild1980

Any help here guys?

Jakpro1

That's weird. How you doin on freon up front? Nice and cold both sides?

Rhaunschild1980

Had it at dealer a few days ago and they checked system, said everything was okay and heater valve needed changed.....bought part from them ($40) and installed last night only to find out that it did not fix my problem. During the dealer's inspection, they checked voltage to the valve and everything was correct. Any ideas? I just moved to Phoenix and have been sweating my n*ts off because of molten hot air blowing from rear!

Rhaunschild1980

And yes....cold from both sides up front!

GT-ER

That's really odd. Unless you made a mistake and left the rear temp high in the digital panel, the system is simple enough that the bypass valve is usually the only thing that goes wrong. I can't think of anything else that could cause this.

taurran

My car sometimes blows hot air in the rear despite being set to cool. What heater valve are you referring to?

izzyz28

It's located behind the firewall, below the wipers. You need to remove the wipers and the plastic panel that goes across to access it. It can be tricky to replace but is certainly doable.

E55AMGGG04

Dam this is bad news i just ordered my valve today. Hopefully i dont have the same issue good luck tho hopefully someone can help

Rhaunschild1980

Update....dealer replaced ac control module in hopes that this would solve my problem and......still have hot air blowing from rear ac after about 15 minutes or so. The tech had the car hooked up to star and said everything was registering fine until the values skyrocketed...what values...I don't know. Back to the drawing board....the SA did mention to me that he hopes they can fix it.....I hope so too! AZ heat is nothing to fool with!

GT-ER

Maybe the new valve is bad? It isn't a very complex system. Maybe they never even changed the valve?

theeddie

would be my guess! or they didnt install it correctly

Rhaunschild1980

Update.....dealer called this morning and they have the shop foreman working on my car...he is stumped. He suggested we try another heater valve and see if that works. Let's hope...I don't know how much longer I can drive the wife's tahoe....big and slow!

Jakpro1

Honestly, that would be bout my only advice as well. There's not that much to that whole system.

Hope this helps brotha!

115 forecast for Tuesday.

Ouch!

Rhaunschild1980

Final Update....(thank God)....got my car back yesterday from dealer and the culprit of my problem was a faulty front SAM unit. Dealer...after a week and a half finally isolated the problem and replaced the module. A/C blows ice cold front and back and now I can finally make it home from my 45 minute drive to and from not soaked from head to toe. Thanks to all for your help and comments....I just can't believe it took the dealer so long to fix problem. On the other hand, warranty company did not cover the part and the dealer felt bad for inconviencing me for so long that they picked up the cost of the part and I paid partial labor cost. That was nice....all in all....I am just happy to not be driving the wife's tahoe anymore. Thanks again!

GT-ER

Good to hear then, It's weird that the sam would go out like this but hey...it's fixed.

Jakpro1

Whats a SAM unit?? WOW, who would have EVER guessed that man!!??

Props to that dealer, he graduates from stealer!

Jakpro1

Signal Aquisition Module????

WTF??

Proving yet again these cars are just like women.

Can ANYONE ever figure them out!!

You just enjoy them in the good times and keep from killing yourself in the bad.