DESCRIPTION
Each radiator fan is made of plastic. It is driven by an electric motor which is retained on a shroud.
Scheme 15
To reduce fan noise, the fan output is two-stepped and can be switched to Low or High according to the load on A/C, coolant temperature, and vehicle speed. This control is accomplished by a circuit as shown below; the output is changed by switching the connection of two motors between serial and parallel instead of using components such as resistors.
Scheme 16
The ECM receives signals from the engine coolant temperature sensor, vehicle speed sensor and A/C switch, and based on these signals, the ECM controls the radiator fan speed to high or low.
Operation example
| Vehicle speed | A/C compressor load | Engine coolant temperature | ||
|---|---|---|---|---|
| Rising: below 94°C (201 °F) Lowering: below 91 °C (196°F) | Rising: between 95 and 96°C (203 and 205°F) Lowering: between 92 and 94°C(198 and 201°F) | Rising: over 97°C (207°F) Lowering: over 95°C (203°F) | ||
| Operation of radiator fans | Operation of radiator fans | Operation of radiator fans | ||
| When accelerating: below 19 km/h (12MPH) When decelerating: below 10 km/h (6MPH) | OFF | OFF | Low-speed | High-Speed |
| Low | Low-Speed | Low-Speed | High-Speed | |
| High | High-Speed | High-Speed | High-Speed | |
| When accelerating: between 20 and 69 km/h (12 and 43 MPH) When decelerating: between 11 and 64 km/h (7 and 40 MPH) | OFF | OFF | Low-Speed | High-Speed |
| Low | High-Speed | High-Speed | High-Speed | |
| High | High-Speed | High-Speed | High-Speed | |
| When accelerating: between 70 and 105 km/h (43 and 65 MPH) When decelerating: between 65 and 100 km/h (40 and 62 MPH) | OFF | OFF | Low-Speed | High-Speed |
| Low | High-Speed | High-Speed | High-Speed | |
| High | High-Speed | High-Speed | High-Speed | |
| When accelerating: over 106 km/h (66 MPH) When decelerating: over 101 km/h (63 MPH) | OFF | OFF | High-Speed | High-Speed |
| Low | High-Speed | High-Speed | High-Speed | |
| High | High-Speed | High-Speed | High-Speed | |
VEHICLE SPEED AND ENGINE COOLANT TEMPERATURE SPECIFICATIONS