Electric Cooling Fan
| ITEM | DESCRIPTION |
|---|---|
| 1 | Fan shroud |
| 2 | Electric cooling fan motor |
| 3 | Electrical connection |
| 4 | Speed flaps |
An electric, variable speed cooling fan is installed in a shroud attached to the rear of the radiator. The cooling fan is operated by a fan control module, integrated into the electric motor, under the control of the PCM through a pulse width modulation (PWM) signal. An electrical connector at the right side of the shroud provides the interface between the cooling fan harness and the vehicle wiring.
The fan control module is provided with:
- A battery power supply from the right EJB
- An ignition signal from the PCM relay in the left EJB
- A PWM signal from the PCM
- A ground connection.
The PCM varies the duty cycle of the PWM signal to the fan control module between 0 and 100% to operate the fan motor in one of four modes:
- Off
- Minimum speed - 750 RPM
- Linear variable speed between minimum and maximum speeds
- Maximum speed - 2820 RPM
The fan control module incorporates a temperature sensor to prevent damage caused by excessive heat at high ambient temperatures. Operation of the fan control module is discontinued if the temperature reaches 135°C (275°F). Operation resumes when the temperature decreases to 120°C (248°F).
Under hot operating conditions, the electric cooling fan may continue to operate for up to five minutes after the engine has been switched off.