Radiator Cooling Fan: Description and Operation

Radiator Fan Control System:

PURPOSE
The Engine Control Module (ECM) controls radiator fan operation based on information from the vehicle speed sensor, engine temperature sensor and the A/C switch. Based on information stored in the ECM's memory it will either operate the fan at high or medium speed or off.

Radiator Fan Control System (Twin-Turbo):

OPERATION
Refer to the chart for radiator fan operating conditions.