1993 Chrysler Concorde defroster comes on by itself and can

1993 CHRYSLER CONCORDE
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ELK067
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Heater problem
1993 Chrysler Concorde 6 cyl Front Wheel Drive Automatic 200+ miles

At startup the defroster comes on high by itself. When that happens none of the buttons on the heater controls work. After a period of time that might range from a couple of minutes to hours, the controls will once again work and I can switch to heat or A/C or vent.
I have been told that this might be a weak vacuum motor or a leaking or broken vacuum line. But I have also been told that it might be a bad resistor. The problem doesn't happen every time I start the car, but it has been happening more and more lately.
What do you think?
Thank You Very Much
Rick
Mar 7, 2009 at 1:47 PM
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JACOBANDNICKOLAS
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Rick:
Do you mean only the defroster works? If so, check for vacuum leaks under the dash that run the vent doors in the HVAC. Also, check for leaks from the engine area the supply vacuum to the heater control.

Let me know what you find.

Joe
Mar 16, 2009 at 1:45 PM
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