Normal Operation

The active, on-demand 4WD system utilizes data from other systems as inputs to the 4WD control module. The 4WD control module uses the inputs to determine the appropriate duty cycle to send to the active torque coupling that delivers the desired torque to the rear wheels. Specific inputs to the 4WD control module are: throttle position output from the PCM, transmission range from the PCM, as well as brake system status and all 4 wheel speeds from the ABS module. Communication between the 4WD control module and other modules is obtained through the high speed controller area network (CAN). If other modules communicate with the diagnostic tool and the 4WD control module cannot, check the power and ground circuits to the 4WD control module before replacement of the module.