General Information

Component Location





General Description

When the ambient air temperature is warm or the airflow across the engine is low, the engine coolant temperature can become hot. If the coolant temperature becomes too hot, it is possible that the engine could be damaged. The purpose of activating the engine compartment ventilation fan is to help reduce the engine coolant temperature to a level that is not threatening to engine performance and maintains the air-conditioning system pressure at safe levels.
Electric fan is responsible for causing air movement around the engine coolant radiator. The amount of air movement caused by the fan is controlled based on the Vehicle Speed, coolant temperature, A/C pressure status, A/C switch request status, and A/C clutch state. A duty cycle is determined based on these input parameters. This duty cycle corresponds to fan speed which correlates to the amount of air movement caused by the fan. The increased air movement enhances the heat exchanger function of the radiator in the confined space of the engine-compartment, thereby reducing the engine coolant temperature more quickly.

DTC Description

The Delphi EMS system provides for a method of electrically controlling when the fan(s) should be activated and deactivated based on a variety of engine conditions, including the coolant temperature, vehicle speed, air conditioning switch status and air conditioning pressure status. As the coolant temperature or air conditioning pressure rises, increased airflow is required to reduce the engine temperature and A/C system pressure. The engine cooling fan(s) are activated to increase airflow across the engine components.
Checking power supply to cooling fan relay to cooling fan module and control signals under detecting condition, if the PCM detects short to ground, to battery or open circuit, PCM sets P0480. MIL (Malfunction Indication Lamp) turns on when the malfunction lasts till consecutive 2 driving cycle.

DTC Detecting Condition





Schematic Diagram