Chrysler Repair/'00 Intrepid: HVAC MTC DTC's 24, 46, 49
QUESTION: The defroster on my 2000 Doge Intrepid does not put out any air. The heater and vents all work very well, but the defroster is a no-go.
Can you offer some repair suggestions?
ANSWER: Hi Dave,
The air flow directions are controlled by an electro-mechanical actuator of the Mode Door.
It could either be out of calibration or not functioning. Do you have the manual temp setting or the automatic temp (digital readout) temp setting control panel?
You could try a self calibration by starting the engine then run the AC full cold for 2 minutes, then run the full heat for 5 minutes, then see if the defroster works.
If that doesn't change the problem let me know which type of control panel you have. There is a diagnostic trouble code procedure that would tell us if the actuator is not working. If so, then I can tell you how to remove and replace it. It is located on the underside of the HVAC housing at the driver's end, and it is the one closer to the cabin of the two actuators on that end. You have to remove some underpanel ducts to see it, but then you simple remove the secrews and drop it down, noting the position of the 'arm' so you can mate the new one back to the door slot.
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QUESTION: Unfortunately, the self-calibration didn't remedy the situation.
The control panel is a manual temperature setting.
Continued thanks for your help on this. Even though the issue is not yet resolved, I already feel that I am much further down the road to correcting it than I was earlier.
ANSWER: Here is how to do the manual temp control self diagnosis:
Engine running but car at rest
Fan on at any speed
Temp control at full cold,
Mode knob at defrost position
AC can be on or off
Press and hold the rear window defrost button until the odometer changes to show "AC00" and there is a beep from the dash and the AC control button starts to blink, then release the rear window defrost button.
Shortly thereafter there will be two digit numbers in the odometer after 'AC'; note the first number then press the AC button to see if there is another code. Keep pressing until the odometer returns to normal function. Let me know what numbers you get.
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QUESTION: The numbers that come up are: 49 46 24
The 24 code says that the Mode door actuator feedback has failed (which means that the body control unit can't know where the door is positioned)and thus it is not being properly moved to the defrost position. But the 46 and 49 codes say that the blend door (temperature control) is shorted to the battery, are you having any difficulty with changing the temp?) and the mode door input signal is shorted to the battery. If there has been no known damage to the wiring between the AC control box and the body computer, then I suggest replacing the mode door actuator on the assumption that it has gone bad. Otherwise I will need to photocopy the wiring diagram pages and postal mail them to you so that you can check the various circuits that are involved to see if you can find some wiring problem or an issue with the body control or the manual temp control themselves.