Blower Switch Resistor

Fig 1: Identifying Blower Motor Resistor Thermal Limiter

Courtesy of FORD MOTOR CO.

The blower motor resistor has the following features:

• The assembly is located on the passenger side of the vehicle on the evaporator housing.
• Three resistance elements are mounted on the resistor board to provide four blower motor speeds.
• Depending on the blower switch position, series resistance is added or bypassed in the blower motor circuit to decrease or increase blower motor speed.
• An overheating protective device (thermal limiter) will open the resistor coil circuit when the temperature reaches 121 °C (250°F) interrupting the blower motor operation in all speeds except HI.
• The thermal limiter cannot be reset and is not serviceable.