Chrysler Repair: 2000 Chrys 300M Climate control locked on frt defrost switchs dont work, control switches, work question


Question
QUESTION: Hello there.  My climate control switches stopped working. They all beep, but the unit is locked on frt defrost only and won't allow heat in until you change to manual, auto runs but no control where or heat. Fuse is good. Any suggestions?  Thank you,
Dale

ANSWER: Hi Dale,
Let me get through with making/eating dinner and be back later this evening.
Thanks
Roland

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QUESTION: Hi Roland

My first name too, but I use my middle name.

No rush, its dark and stormy here and it's not going anywhere tonight.
If I wasn't clear on my problem, let me know and I will try give you more infor.

Dale

ANSWER: Hi Dale,
On the LH body cars with ATC you can do a self-diagnostic test on the unit for fault codes: set the temp for 75, and with the engine running but the car at rest simultaneously push the floor, mix, and defrost buttons (lower, upper, upper on buttons 4,5,6 respectively) and hold them until the display starts to blink. Then release the buttons and wait for any two digit number to appear in the display (between 23 and 51). If you get a number then press the panel button (upper of #4) to see if there is another number. Keep trying panel until no more numbers come out. If not, then the unit will revert to normal function. Let me know the fault code numbers that appear and we'll go from there.
Roland

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

QUESTION: Hi Roland,

Well, I ran the test as stated and the only number that came up was 24.  Ran it twice and got the same number.

Side question:  I was thinking of buying a Clinton repair book for the car.  Do you know, will it give me the same type of information you did?  I ran a recall report and got a ton of notices on it, way too many to do anything about and I have never gotten one of them even though I should be registered with Chryl.

This has been a great car for me with only one major repair, the transmission locked up last year requiring a replacement be installed after having it towed from home to shop.  Great service from our local Ammco Dealer. (just a tidbit of trivia)

Answer
Hi Dale,
The code 24 comfirms your symptoms, the mode door is not moving to change the distribution as requested, It is on the bottom side of the HVAC unit,  but you will have to remove some ducts, etc. to get to it.
The mode door actuator is on the driver's side of the unit, on the the bottom and rearward (toward the rear of the car) of the other actuator nearby which is for the blend air door.
Disconnect the battery
Remove the left and right under panel ducts from the lower edge of the dash
Remove the floor console
Remove center floor heat adapter duct
Remove rear seat heat forward adapter duct
Loosen center support bracket and pry rearward to gain access to the actuator.
Remove actuator retaining screws (two from the left side, one from the right side). Pull straight down. Upon removal note the position of the actuator tab because it is keyed to the door. See if the door moves freely by rotating the tab. If so, then the actuator is likely the issue.
The wire colors are: dark green/yellow, pink/dark blue, yellow/white, dark blue/gray, and brown/white for purposes of ID as compared to the nearby blend door actuator.
On the manual, I would try for the Chrysler factor service manual for that is far better than a Chilton. Check on eBay searching for Chrysler service manual until one comes up for '00 LH body cars at a reasonable price, say $15-20 including the shipping. An '01 manual is likely to be the same, but after that there are some changes that were made.
Roland

PS: Disconnecting the battery is just 'boiler plate' in such a manual when dealing with anything electrical. There is little likelihood of damage/danger if you skip that step. The duct work will be fairly obvious once you get going on the project. Thanks for the rating and nomination.