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Chrysler Repair/HVAC Mode door acturator: 300M


QUESTION: I found the gray 14-pin connector to the bcm and there was good continuity to Pin 8.  All the continuity checked out fine.  Tomorrow, I'm going to check the actuator again.

I'm sending this private because I could not add any additional comments to my last question.

ANSWER: Ok, see if you can free-up the door too.

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

QUESTION: What is the best way to clean the mode door?  I tried blowing it with an air compressor and wiping it with a cloth.  There looks like there might be some dirt build up or it might be the rubber around the edge to make it air tight that is causing the door to bind.  I was able to get the actuator to work a couple times with a couple of good test.  But then the actuator made a several clicking sounds and that was it.  I don't know if I spray some WD-40 or other lubricant into the mode door will help break up dirt and loosen up the door. I don't think I can unscrew the bottom to get a better view of the door.

Should I rate you for each of the question I've asked?  If so, you can answer my above comment on the public question so I can rate your help.

I really do appreciate your help.

ANSWER: Hi Lynn,
The two sprays to consider are WD-40 or silicone spray. I would lean toward the latter if there is no evidence of a greasy/dirty sort of build up for which WD-40 would be my choice.
If you think it may just be a rubber/plastic interface issue then silicone would be better.
The silicone also would likely be likely to damage the rubber, I believe.
I haven't seen any suggestion for how to remove the door without taking out the entire unit.
On the rate/nominate question, please feel free to do so for each of my answers, up to 5 in a month because beyond that they are not counted. Thanks for asking.

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

QUESTION: I finally found the problem:

1)Based Rolandís recommendation, I tried troubleshooting the wiring from the controller to the bcm.  All the wiring checked out fine so I knew the problem was not in the wiring.  I was very happy I did not have to purchase a new bcm

2) Next I checked if the door was binding up.  I could turn the round dial by my but it did feel like it was binding in one location so I decided to clean the vent door.  First, I tried cleaning the door with my air compressor but that did not make a difference.  Next, I took a rag and wiped the inside along the walls.  The rag was dirty and it did seem to help a little but it was not enough.  There is a little plastic lip on the side closest to the firewall of the door that need cleaning.  It was hard to reach up into the door to clean that little piece of rubber but that is what was binding the door.  As soon as I cleaned that rubber piece, the door dial was very easy to turn.

Lesson learned:
I ended up purchasing a used mode door actuator since I went through 3 band new OEM mode door actuator; however, my original mode door actuator still works.  What I realized from all my troubleshoot, as soon as you run a diagnostic and it registers the code 24/33 your mode door actuator is cut off until the diagnostic runs a fully functional test.  So, as soon as the diagnostic registered no errors the original mode door actuator begin working like normal.

Hi Lynn,
Thanks so much for telling me (and ideally other 300M owners) about your experience in repairing the binding up mode door. You got to the bottom of the problem, learned a great deal and shared the information.
Also, thanks so much for the ratings/nominations/kind remarks.

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Roland Finston


Get a Free Fast answer to your repair question about a Chrysler/Dodge/Plymouth car, minivan, SUV, or truck. Problems with electronically controlled engines and transmissions as well as body wiring problems are my specialty. This free troubleshoot advice forum helps you diagnose faults, minimize repair costs or do-it-yourself.

I answer questions seven days a week and respond to you in about 30 minutes. "Maxed Out" means I am answering another question, briefly unavailable, so try again later.

I have do-it-yourself experience (50+ years) and a library of 100 1982-2012 Chrysler factory shop manuals and 20 multi-manual Chrysler Corp. CD's.

I was voted "Top Expert" 2010-2015, here at AllExperts, and have answered 20,000+ questions.


Five decades as a 'do-it-yourselfer' on domestic and imported cars.

Yahoo Autos Group called The Chrysler Lebaron Club (co-moderator)

Advanced degrees in Physics/bruised knuckles

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"Top expert" of 2010, 2011, 2012, 2013, 2014 and 2015 here at Allexperts. Quickest "average response time" at Allexperts (currently no. 1).

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