Quiky One

Need some expert help here...The car has 11xk miles and has never had trouble before. When on "auto" the car will switch from cold to warm. Then when you restart the car it works fine...

Any help?

Thanks Jason

Dewey

iTrader: (1)

sounds like a problem with your HVAC unit. maybe someone with experience with this problem will chime in.

53bowtie

iTrader: (6)

It would help to know what kind of vehicle it is?? It could be either a control unit or actuator bad.

AKlowriderZ71

iTrader: (22)

Could you post up the year, make, and model?

Quiky One

Sorry, 2004 Yukon Denali with the auto climate control.

Thanks Jason

53bowtie

iTrader: (6)

If it does it only on auto I would say it would be a controller issue in the dash. If it does it no matter the setting on the controller then it is going to be your blend door actuator.

Quiky One

Thanks. How many "blend door actuators" does this vehicle have? I would assume one. Also, where is it located?

AKlowriderZ71

iTrader: (22)

Jason, if you look on the headliner, you will see little things that look like small speaker grilles. They are HVAC air temp sensors. Have you ever heard any of them making clicking sounds? They seem to go bad often, and can make the HVAC system do strange things.

At any rate, the system is computer controlled, and likely has a failure code stored in the computer. If you can find anybody with a Tech2 scanner, try to get the code. That is the best place to start diagnosing.

Prime Power

I had this. Unplugged the battery and problem went away. Been almost a year now.