COOLING FAN MOTOR COMPONENT CONSTRUCTION/OPERATION

Construction

• The cooling fan motor component is installed on the back of the cooling fan.

• The cooling fan motor component consists of the fan motor and fan control module.

Operation

• The fan control module drives the fan motor based on the cooling fan control signal sent by the PCM according to the engine coolant temperature, vehicle speed, battery voltage, A/C pressure switch is on or off, and whether the A/C magnetic clutch is on or off.

• The fan control module allows continuously variable control of the fan motor rotation rate reducing fan operation noise and power consumption. If there is a reversed power connection, the fan control module incorporates protection against reversed polarity. The motor reacts to the reversed power connections with unregulated, high-speed rotation in the wrong direction.

Fail-safe function

1. Over-current fail-safe

- If current to the fan motor exceeds the specified value, the fan control module stops the fan motor for a specified period of time.

2. Over heat fail-safe

- If the internal area of the fan control module exceeds the specified temperature, the fan control module stops the fan motor for a specified period of time.

3. Input signal open circuit fail-safe

- If there is an open circuit in the wiring harness between the PCM and the fan control module, the fan control module stops the fan motor.

4. Reversed polarity fail-safe

- If there is a reversed power connection, the fan control module incorporates protection against reversed polarity. The motor reacts to reversed connections with unregulated, high-speed rotation in the opposite direction.