Chrysler Repair: 2000 LHS ATC Problems, automatic temperature control, ac icon


Question
QUESTION: The automatic temperature control is not working correctly.  The display seems to work fine.  The problem is the air blows constantly out of the defrost vents and the temperature doesn't seem to change.  It will not change in auto or manual. The display shows that it should be changing to the middle vents or floor vents and the AC icon even comes on but it never changes from blowing out of the defrost.  The air just seems to get warmer and warmer coming out of the defrost vents.

ANSWER: Hi Cheryl,
There is a self-diagnostic capability within the unit.
With the engine running and the car at rest, set the temp to "75>sno F" reading. Then simultaneously press and hold the floor, mix, and defrost buttons (lower/upper/upper of the 4th,5th,6th buttons) and the panel should start blinking. Then release the buttons simultaeously and wait until the blinking stops and a 2-digit number between 23 and 51 appears. Note the number, then press and release the 'panel' button (upper 4th button) and see if an additional number appears. If none that is the end, if so press again until panel returns to normal and you have all the two digit numbers recorded to share with me. Using those numbers I will tell you what is wrong and what needs to be done.
Please 'rate' my answer (see below).
Thanks,
Roland

---------- FOLLOW-UP ----------

QUESTION: I got a 24.

Answer
Hi Cheryl,
That code corroborates the symptom in that it says the feedback signal from the "mode door" actuator, which is what moves the air to various selected outlets, is absent. Likely the actuator is the problem rather than the wire that carries the signal betweeen the actuator and the body control module which is under the dash also at the left end. There is a several step procedure to get access to the actuator which I can describe, and then you simply unplug, drop it out the bottom of the distribution box and replace it with a new one. Let me know if you want to do this fix yourself and I'll list the steps for you or I can copy a page from a CD I have and attach that to an email I will send to you directly. Let me know your email address if you want that, but don't use the @ symbol, instead use 'at' or the address will be automatically erased.
Please 'rate' my answer (see below).
Thanks,
Roland