A/C only on LO, otherwise - hot air

CenTexHutch · October 1, 2016

Just got my 2015 LTZ about 3 weeks ago. It has 53,000 miles. Suddenly a/c only blows cold when set on LO. One notch up, to 60 degrees and you can hear thing shift behind the dash and it starts to blow heated air. Not just warmish air, heated - as if I have the heater on.

Brianibew · October 2, 2016

Just a stab at this, but my 2003 Silverado with auto temp controls did this as well. It was the aspirator that failed. It's a very very small fan that samples the cabin air temp so the auto control can, well, work in auto. On the 03, it was located in the headliner above the drivers head.

2016 Sierra Owner · October 2, 2016

What he said above. The aspirator is still above your head in the headliner. Small square grille. or is the outside temp reading correctly? I believe in auto it takes the outside temp into consideration as to heat or cool to the degree you set in auto.

CenTexHutch · October 2, 2016

I've been in and out of the truck about 10 times today and all day the a/c has been performing normally. Outside air temps are about the same. I'll just keep my fingers crossed. Love the truck otherwise.

Brianibew · October 2, 2016

Forgot to mention that the aspirator is a very cheap and easy to replace part if you start having issues again, take care.

JRL1164 · October 2, 2016

Where is this thing actually?

Brianibew · October 3, 2016

If you have auto climate controls, the aspirator is above the drivers head behind the small "vent" in the headliner. To access it, open the drivers door, pull the headliner down just enough to gain access the the aspirator, unplug and replace.

JRL1164 · October 3, 2016

If you have auto climate controls, the aspirator is above the drivers head behind the small "vent" in the headliner. To access it, open the drivers door, pull the headliner down just enough to gain access the the aspirator, unplug and replace.

Thanks, I thought that was the mic for calls. Thanks. I don't guess anybody has a PN?