Radiator Cooling Fan Motor: Description and Operation

On models equipped with electric engine cooling fans, the battery ground cable should be disconnected whenever underhood service is performed.

Electric engine cooling fan (typical):

On all models except 1985---87 equipped with 2.2L/4-135 and 1986---87 2.5L/4-153 engines, the fan is controlled by a fan switch which is located on the radiator. The switch will automatically turn on when coolant temperature reaches approximately 193 to 207 degrees F. On all models with A/C, when the A/C system is in operation, the fan motor will operate continually regardless of engine coolant temperature. When the ignition switch is turned off the fan motor will stop operating, except on models equipped with 2.6 L engine and air conditioning. On models equipped with 2.6L/4-156 engines and air conditioning, and others, the fan will remain operating with ignition off for approximately 5 to 10 minutes if ambient temperature at radiator is above a predetermined level (after-run fan).

On 1985---87 models equipped with 2.2L/4-135 engines and 1986---87 models equipped with 2.5L/4-153 engines, the fan is controlled by the on-board computer. The computer shuts off the fan motor automatically when it is not needed on vehicles less air conditioning, or when the A/C is shut off on vehicles with air conditioning. The fan motor is always on when the air conditioning compressor is running. With A/C off or on models less A/C, the fan runs with vehicle speed above 40 mph only if coolant temperature reaches 230°F and will turn off when temperature drops to 220°F. At speeds below 40 mph, the fan switches on at 210°F and off at 200°F. The fan motor does not operate when the ignition is turned off.