Radiator Fan Control

Cooling Fan Modules:

Fan control is accomplished in two ways.
- The fan always runs when the compressor clutch is engaged.
- The fan is also turned on by the temperature of the coolant which is sensed by the coolant temperature sensor. The coolant temperature sensor sends the message to the Powertrain Control Module (PCM). The (PCM) turns on the fan through the Pulse Width Module (PWM). Switching through the (PCM) provides fan control for the following conditions:

1. Fan will not run when cranking engine no matter what coolant temperature is.
2. Fan will run when A/C clutch engaged and low pressure cutout switch is closed.
3. At vehicle speeds over 40 mph, fan will run only if coolant temperature reaches 230°F (110°C) and fan will turn off when temperature drops to 220°F (104°C).
4. At vehicle speeds under 40 mph, fan will run when coolant temperature reaches 215°F (102°C) and fan will turn off when temperature drops 200°F (93°C).