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Radiator Cooling Fan: Description and Operation

Circuit Description
The engine control module (ECM) or engine/ transaxle control module (PCM) controls the operation of the radiator fan and the condenser fan. The control module monitors coolant temperature through engine coolant temperature sensor. The module also monitors A/C operation through the A/C ON input and A/C pressure switch input . Using these inputs, the module will ground the coil of the appropriate relays to provide low speed, middle speed and high speed fan operation. For more detailed fan operation, refer to the cooling fan logic table.