Radiator Cooling Fan Motor: Description and Operation

The cooling fan will operate if the electrical connector to the coolant temperature switch is disconnected with the ignition switch in the On position. When servicing cooling fan components, disconnect battery ground cable.

Fig. 1 Electric engine cooling fan wiring circuit:

DESCRIPTION

The electric cooling fan is located behind the radiator. Cooling fan operation is controlled by the coolant temperature switch, located on the thermostat housing. When coolant temperature leaving the engine is approximately 207°F, the coolant temperature switch will open. When the coolant temperature switch opens, the cooling fan relay de-energizes, allowing the relay points to close, Fig. 1. When the relay points are closed, the ground circuit for the cooling fan is complete, and the fan motor should operate. When the coolant temperatures are below approximately 194°F, then coolant temperature switch closes, completing the relay coil circuit. When the relay coil circuit is complete, the relay points will open, de-energizing the fan motor. Voltage is supplied to the fan motor through the ignition switch and an 80 amp power fuse. Voltage to fan motor relay is supplied through the 10 amp gauge fuse which is also fed from the ignition switch. On models equipped with air conditioning, an auxiliary condenser cooling fan is also used. Whenever the A/C compressor clutch is in operation, both the engine cooling fan and auxiliary condenser cooling fan will operate. When the A/C compressor clutch is not in operation, the auxiliary condenser cooling fan will stop operating and the engine cooling fan will return to the control of the coolant temperature switch.

Fig. 2 Engine cooling motor replacement:

COOLING FAN REPLACE

1. Disconnect battery ground cable.
2. Disconnect cooling fan electrical connector, then remove fan shroud to radiator attaching screws, Fig. 2.
3. Remove fan and shroud assembly from engine compartment.
4. Remove fan motor to shroud attaching screws, then remove fan motor.
5. Reverse procedure to install. When installing, ensure fan shroud engages clips located at bottom radiator.

Fig. 3 Coolant temperature switch location:

COOLANT TEMPERATURE SWITCH REPLACE

1. Disconnect battery ground cable.
2. Drain cooling system.
3. Disconnect electrical connector from coolant temperature switch, Fig. 3, then remove switch from thermostat housing using a suitable wrench.
4. Reverse procedure to install.

Fig. 4 Cooling fan relay location:

COOLING FAN RELAY REPLACE

1. Disconnect battery ground cable.
2. Remove screw attaching cooling fan relay to inner fender panel, Fig. 4. The cooling fan relay is located at the left front corner of the engine compartment, between coolant recovery bottle and horn relay.
3. Separate relay from electrical connector and remove.
4. Reverse procedure to install.