Cutlass Ciera Cruiser V6-3100 3.1L MFI VIN M (1994)
Radiator Cooling Fan Motor Relay: Description and Operation
Cooling Fan Control Circuit
Purpose
The engine is equipped with two PCM controlled cooling fans. The secondary fan or auxiliary cooling fan is used for heavy duty cooling with A/C.
Operation
Primary Fan - When the engine is running, the PCM will turn "ON" the primary cooling fan for any of the following reasons:
^
Diagnostic Trouble Code (DTC) P0117, P0118 or P1530 is set.
^
Engine coolant temperature is 106°C (223°F) or greater
^
A/C is requested and vehicle speed is less than 50 mph
^
A/C refrigerant pressure is 190 psi or greater with A/C requested
Once the primary cooling fan is enabled, the PCM will turn the primary cooling fan "OFF" when:
^
Engine is turned "OFF"
^
Engine coolant temperature drops to 102°C (216°F) or less
^
A/C refrigerant pressure drops to 140 psi or less with A/C requested
Secondary Fan - When the engine is running the PCM will turn "ON" the secondary cooling fan for any of the following reasons:
^
Engine Coolant Temperature (ECT) is 112°C (223°F) or greater
^
A/C is requested and vehicle speed is less than 50 mph
^
A/C refrigerant pressure is 246 psi or greater
Once the secondary cooling fan is enabled, the PCM will turn the fan "OFF" when:
^
Engine is turned "OFF"
^
When the engine coolant temperature (ECT) sensor indicates the coolant temperature has dropped to 108°C (226°F) or less
^
When the A/C refrigerant pressure drops to 196 psi or less
