Do you have an auto system or manual controls? Based on your statement I am assuming you have an auto system. If this is the case, it could be the module.
However, this could also be the blower motor processor. If you look at the wiring diagram the HVAC module tells the processor what to do by adding a load to the ground side of the blower motor. By doing this is decreases the voltage that the blower motor uses which slows down the motor.
Can you tell me where you measured this voltage? Looking at the diagram you should have voltage there because the blower is hot at all times. This is a ground side control so the motor will not turn on until the module grounds the circuit.
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Wednesday, December 11th, 2019 AT 3:51 PM