The Powertrain control module (PCM) controls the operation of the cooling fans. This is accomplished by providing a ground path for the cooling fan relay coils within the PCM. The relay contacts will close and complete the circuit between the Maxifuse® in the underhood electrical center and the fan motors. Whenever there is a fan "on" request, both fans will be running. A coolant temperature switch activates the fan motors. A transducer can also activate the circuit, depending upon A/C request or A/C compressor head pressure to the condenser.
See Figure 1
For electric cooling fan testing procedures, please refer to Engine and Engine Overhaul of this repair guide.
Removal & Installation
- Disconnect the negative battery cable.
- Disconnect the sensor electrical lead and unscrew the sensor. The sensor can be found on the right side of the engine.
- Install the sensor or relay and connect the electrical lead.
- Connect the battery cable.
See Figures 2 and 3