FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Radiator Cooling Fan Control Module: Description and Operation

OPERATION
The Powertrain Control Module (PCM) monitors coolant temperature, vehicle speed, and air conditioning status to determine if cooling fan operation is required.

When the PCM determines a need for cooling fan operation, it sends a signal to the Constant Control Relay Module (CCRM) to run the fan at the required speed.