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1994 LHS heat won't shut off

My mother in-law has a 94 Chrysler LHS, 3.5 V6, auto, 66k. Called me today to say heater is blowing very hot air at her feet. She said she tried turning off, changing temp. and there is no change. This car has climate control and I assume the problem is with that but I do not know how to test.

First things first. Check the temp gauge on the dash. Make sure the engine isn’t overheating. Unlikely to be the cause, but if it is, you want to catch it fast to prevent possible engine damage.

Hopefully someone here has some Chrysler climate control experience and can chime in with something helpful to address the problem, assuming it isn’t an overheating engine.

Best of luck.

The easiest way to fix this is likely to go on ebay and purchase a climate control module–the part that goes in the dash and has the knobs and buttons. You can likely find one for $50 or less. Changing it out is very simple. You pry off the trim panel around the climate control and radio. Remove the phillips screws holding in the CC unit, and disconnect the electrical connectors in the back. Plug in the new unit and put everything back together.

If you want to try resetting it, this may help:

On cars with automatic climate control: To enter diagnostic mode, set the temperature to 75F, press the the off button. Press Floor, Defrost\Floor, Front Defrost simutaneously and hold them for 3-5 seconds until the temperature display begins to flash. The system will go through a testing procedure where the various modes and fan speeds will be cycled through. When done, if there are any fault codes, they will be displayed on the temperature display. To exit the test mode, select any other mode by pushing a button. Frequently this will temporarily fix a problem like yours. Also helpful after doing this is to slowly turn the temp all the way up, then all the way back down to cool. This allowed me to be lazy and ignore the problem with mine until I got fed up and just replaced it. If this doesn’t work, I’d just replace it. Good luck.

Like oblivion said, the problem is likely in the control panel. These have been discontinued through Chrysler, so finding a good used part is your only answer.

and when Chrysler did have them on the shelf they sold for about 450.00