CTS heat on the blink

[erwhite]

I recently purchased a 2003 CTS only to find that the heat is one sided. The driver side heat is only half functional. Is there 2 sensors in the vehicle for heat or 2 separate thermostats? My limited warranty is about to expire. Any suggestions?

[Marlin]

If under warranty take it in now.

But the CTS has dual zone heat/ac. Could be a door problem as well.

Is it just the temp that is not right or lack of airflow?

[Custom88]

There are two separate air-mix doors for the climate control system. one for driver's side, one for passenger's. If one of these door mix motors fail, the door will be stuck in one position. This is a common problem amongst cars with electronically controlled climate controls. (Manual systems just use a cable that runs to the knob/slider.) Definitely take it in and have the dealer look at it before the warranty expires. They can hook a TECH II to it and extract the codes from the climate control, which most other shops/businesses cannot do.

[erwhite]

The air flow is fine. But I will set the Temp up to 90 and not get 1/2 the heat. I will definitely take to the dealer and question the door mix motors and see if that could be part of the problem. Thanks for replying. I am new at this but I hope that this will help solve my problems before the warranty expires.

[VicCTS]

Did you ever find out what the problem was? I do not have heat on the driver's side and out of warranty. Thanks.

[ewill3rd]

The last one of these I saw was a plugged heater core, not pretty.
I have pictures at work.
I tried flushing the thing 9 ways from Sunday and it just wouldn't clear out.
We finally had to replace the core.
It certainly could be a temperature door motor problem but it needs to be checked.

[VicCTS]

Thanks!