Chrysler Repair: 93 concorde atc blows hot air only, air distribution system, check fuse


Question
ATC is not working and high heat is on all the time

Answer
Hi Andre,
It could be that there is a problem with the control unit itself, but before concluding that a test should be done to see if the computer has recognized any problems and described them in the form of two digit fault codes stored in its memory. Did someone do such a inquiry? If so, what numbers did they get? If not you can do the readout yourself:
The unit does have a self-diagnostic capability. The engine has to be running and the car not in motion to do the test. Simultaneously press the floor, mix, and defrost buttons, (the 1st,2nd and 4th on the top row) and see if the display unit begins to blink. Release the buttons when it has started to do that and then after it blinks for a while longer watch for two digit numbers to appear on the readout. Those are the fault codes. If the first number appears and stays in place, push on the first button in the bottom row (panel) to continue the readout. At the end of the readout the unit will return to normal settings.
Then write back with the number(s) and also tell me more about exactly what is wrong with the function of the unit.*
If the head unit doesn't respond at all, then check fuse #6 under the dash. There is also a 12V supply line to the control that is directly connected to the battery on a black/pink wire on the green plug on the rear of the control unit that should be checked to verify that you are getting that power to the control unit.
I would do a thorough readout before buying a new control unit. It may be a part in the air distribution system itself rather than the computer that is the problem. And you also might find a working used unit at a wrecking yard.
Roland
*The code numbers range from 23-36. You can also get a decoder list at www.allpar.com/fix/codes_climate.html