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Q: My 1999 BMW blower comes on whenever I put keys in the switch and turn the motor on.

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My 1999 BMW blower of the AC or heater comes on whenever I put keys in the switch and turn the motor on.

My car has 270000 miles.
My car has an automatic transmission.

A: Hi there, thanks for writing in. If this co...

Hi there, thanks for writing in. If this comes on right when the car is turned on, then most of the time it is caused by a bad blower resistor module. This module fails internally and causes this to occur. I usually test the module first to see if it has failed as it can also be the fan control from the HVAC module. If you want to have this blower motor problem fixed, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose and repair this.

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