Hi to all,
I search some on this site and have no clear answer to my problem. I have a 2000 300M with about 114K miles. The wife really like this car. It has been relatively a good car, only normal wear items, suspension, steering parts brakes, oil changes.
The trouble started about 6 months ago. Long story short, I had a "sleeping" ATC, a good dash slap would wake it up. I tried a JY atc, it had the same problem (what are the odds?). I re-soldered the resistors and voltage regulator and that seemed to work. I then came up with a "code 24" mode door actuator feedback failure and the ducts would not switch from defrost to floor or vents. I then replaced the mode door actuator (MDA) with a mopar replacement. Still have the code 24. I sent the ATC out and had it "refurbished" just to make sure I had a good one (2 year guarantee). I installed it today, guess what code 24 still there. Each time I did the service work, I disconnected the battery in order to reset the computer. I am currently running with out the MDA in place, I have manually positioned the vents to get some warm air to the defrost and floor so we can drive it. I have also watched the MDA while doing an code scan (three button methode on the ACT), the MDA will rotate, clockwise only. It will turn during some scans and not others. Funny thing is, with no MDA plugged in, the only code I get is 24. The situation has deteriorated to where the temperature will not work correctly either.
I guess the questions I have are, what provides the feedback? Is it part of the MDA or is there other sensors buried in the dash tha monitor the mechanical linkage? Is this a bad Body Control Module (BCM)?
I hope someone here recognizes this strange series of events and can provide some guidance. I hope this isn't a $$$$ problem

 

I have a dodge stratus that had a similar problem, and it was the mode door actuator switch that was causing it to only blow out the defrost vent. I swapped it for another that I got at the junkyard, and it has been working great since.

 

i also get a code 24 cannot switch from vent to defrost,was not control head nor actuator there was a tsb in 04 for the issue that calls for the system to be recalibrated?goin to try disconnect battery today and see what i get

 

still have not got fixed goin tuesday to a chrysler mechanic any have a good fix for this?

 

Hi all,
I picked up a 1999 300m that was showing code 24. I picked up a actuator from the wrecking yard and plugged it in while it was laying on the floor. I couldn't get it to work so I tested all the wiring for continuity from the head down to big white plug just above the gas pedal. I Continued testing the wiring past the plug to the actuator.. Then tested all the wires from the plug to the bcm. Still couldn't get it to work. I tried a different bcm and head unit with no luck. Checked all fuses under the hood and dash.
I noticed that when I connected the battery and started the car the actuator would turn then stop but after stopping I couldn't get it to move by pressing the buttons on the head unit.
I read in another forum that upon reconnecting the battery and turning the key on causes it to move into position to get in sync with the head unit so then I thought " maybe it has to be installed to get in sync with the head unit because the entire time its been unscrewed and laying on the carpet.. I just wanted to make sure it worked before reinstalling it with the 3 screws. So I realigned the gear with the blend door wheel, got it back into position and reinstalled the screws. I reconnected the battery cable, started the car and watched it go through the initial cycle just as it did when it was laying on the carpet. But after it completed it's cycle I pushed the buttons on the head unit and it worked!
So I learned that the actuator has to be installed in order for the head unit to operate it. It has to complete a set up cycle by turning the blend door wheel to get in sync with the head unit before working.. I hope this helps anyone experiencing the same issues.

 

Hi. I have been following the response to this post to try and get a solution to the following issue. I have a 2000 Chrysler 300M. I have recently had the AC repaired. The evaporator core, AC control module, and vent door actuator have all been replaced. Everything worked perfectly for a while but now the vents will not switch from the floor/vent mix. I ran a diagnosis check on it and it showed a code 24. I was just wondering if there is a quick and easy fix for this, or if I need to take it back to the shop. Thank you all for any assistance in this matter.