What controls the heat
Could be a servo motor sticking for the temp control.
Or a resistor board. There' s a different resistance for each blower speed. When this board gives out, only certain speeds may work.
Definitely sounds like a resistor! Located next to the blower motor in the HVAC housing on the passenger side under the dash. Autozone part # CR153... $60.00..... may actual be cheaper going with OEM, call your local Dodge dealer.
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