Electrical Fan Operation

The engine cooling electrical system consists of:
^ Fan control (FC) relays
^ Engine Coolant Temperature Sensor (ECT sensor)
^ Water temperature indicator sender unit

Two high cooling FC relays and one low cooling FC relay govern the operation of the engine cooling fan motor. The relays are located within the LH engine compartment relay panel. The FC relays operate under the following conditions:




A/C Switch Is OFF





A/C Switch Is ON (Front Climate Control Assembly Is In Any Mode Except OFF), A/C Pressure Cut-Off Switch Is OFF.





A/C Switch Is ON (Front Climate Control Assembly Is In Any Mode Except OFF), A/C Pressure Cut-Off Switch Is ON.


The high fan control relay 2 is a safety relay, ensuring engine cooling fan motor operation in the case of a high fan control relay 1 failure.

The ECT sensor measures coolant temperature at the water hose connection and supplies this information to the Powertrain Control Module (PCM). If the ECT sensor fails, both high fan control relays will activate the engine cooling fan motor.

The water temperature indicator sender unit is also located on the water hose connection. The water temperature indicator sender unit responds to coolant temperature and provides this information to the temperature gauge.