2004 Malibu LS - Heater wont turn off [Archive] - Chevy Malibu Forum: Chevrolet Malibu Forums

: 2004 Malibu LS - Heater wont turn off

11-12-2010, 10:52 AM

I would appreciate any help greatly with this issue.

I have a 2004 malibu classic ls. The other night turned the heater on (or temp knob to red) and now I want to switch back to cold ac and the heater still is blowing hot air.

The ac worked great until I turned the heater on and now it wont go back to cold air. I have done some reading and I think it might be that the heater door is stuck in the Open position. I have taken my dash apart partially to try to find where this heater door is to manualy close it but cannot find it.

Please help, or if you know of a fix that isnt the heater door please reply.

Thanks again!

11-12-2010, 11:34 AM
The air temperature door on your Malibu is controlled by the air temperature actuator motor. I'd start with simple things like fuse #46 (HTR A/C IGN) in the engine compartment fuse block and go from there. See the wiring diagram at http://cid-54465800aad91b49.office.live.com/self.aspx/pub/va186315.pdf.

11-12-2010, 01:50 PM
Ok I found the fuse you were referring to, it was in the interior of the car and it is fine not blown. I'm pretty sure it is the heater door that is not functioning properly. I believe there is an actuator that open and closes it just like the defroster.

I have the entire dash apart and still cannot figure out where the heater door is and how to get to it and the actuator that controls it.


11-12-2010, 04:19 PM
You must have a Malibu LS and not "malibu classic ls," then. The air temperature actuator is on the left side of the HVAC case. Duck under the dash on the driver side and look to the right and up. See component 4 in the diagram at http://cid-54465800aad91b49.office.live.com/self.aspx/pub/Left%20Side%20of%20HVAC%20Case.gif. It's secured with two bolts like in the next diagram at http://cid-54465800aad91b49.office.live.com/self.aspx/pub/Air%20Temperature%20Actuator.gif.

11-12-2010, 08:33 PM

Thank you very much for all the info and help.

I found the actuator and removed it and found that the arm the actuator turns to move the heater door was frozen up. The actuator was actually fine but could not turn because the arm was locked up. A little wd 40 and a wrench to loosen it got it working and I am pleased to say that I am back to cold AC!

Thanks again!


11-12-2010, 09:07 PM
Glad to hear.:) It's always nice to hear success stories. And, belated welcome to the forum.