Radiator Cooling Fan Motor: Description and Operation

Voltage is provided at all times to the radiator fan relay and the radiator fan control module. For the module, voltage is also provided in ON (II) or START (III). The module provides power to the radiator fan relay when the ignition switch is in ON (II) or START (III) and for 2 minutes after the ignition is switched OFF. The radiator fan relay is energized whenever the BLU/RED wire is grounded. The BLU/RED wire can be grounded by the engine coolant temperature switch A, the A/C switch and fan switch, the Powertrain or Engine Control Module (PCM with A/T or ECM with M/T), or the radiator fan control module.