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Q: Loss of voltage at blower motor when it is connected to regulator - regulator is brand new

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I have a complete loss of voltage when I connect the blower to the resistor - resistor, blower brand new - blower works when attached to battery, voltage at the resistor is between 10.7 and 12.5 when car is running but as soon as I attach the blower motor to the resistor, it drops to zero. Tried connecting blower direct to wires from switch, which had voltage, bypassing resistor, but the voltage still drops to zero.
My car has an automatic transmission.

A: Hi there. The issue you are having is not ...

Hi there. The issue you are having is not the resister, but rather the switch. The switch contacts are shorting out back to the battery causing the a/c blower not to work. I recommend replacing the a/c blower switch. If you need further assistance troubleshooting your vehicle, then seek out a technician, such as one from YourMechanic, that can assist you with replacing the switch.

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