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Blower Motor Resistor: Description and Operation

BLOWER MOTOR RESISTOR

The blower motor resistor:
- is located on the heater core and evaporator core housing near the blower motor.
- has three resistor elements mounted on the resistor board to provide four blower motor speeds.
- depending on the blower motor switch position, series resistance is added or bypassed in the blower motor circuit to decrease or increase blower motor speed.
- has an overheating device (thermal limiter) that will open the resistor coil when the temperature reaches approximately 184°C (363°F), interrupting the blower motor operation in all speeds except high.
- is serviced as an assembly. The thermal limiter cannot be reset and is not serviceable.