
Signs of a Faulty Blower Motor Resistor
- Fan stuck on One Speed
- Fan Only Works on Certain Speed Settings
- No Air Blowing From the Vents
What is a Blower Motor Resistor?
The blower motor resistor is an electrical component that controls the blower motor’s fan speed. The climate control knobs or buttons are set to send a signal to the resistor, which then regulates the electrical power being sent to the blower motor to either operate at full power, or at a reduced speed. Some vehicles may also have a separate rear blower motor resistor used to control the zone climate in the rear passenger area.
The fan speed control is an integral and frequently used setting in the climate control system, and due to this high usage the blower motor resistor may wear out or short circuit over time. If you notice the blower fan only working on one setting (most commonly the highest speed), or not blowing at all, the blower motor resistor may need to be replaced.