Normal Operation

The All-Wheel Drive (AWD) system uses data from other systems as inputs to the 4X4 control module. The 4X4 control module uses the inputs to determine the appropriate duty cycle to send to the Active Torque Coupling (ATC) solenoid (part of rear axle) that delivers the desired torque to the rear wheels. Specific inputs to the 4X4 control module are: accelerator pedal position output from the PCM, brake system status and all 4 wheel speeds from the ABS module. Communication between the 4X4 control module and other modules is obtained through the High Speed Controller Area Network (HS-CAN). If the 4X4 control module loses communication with, or receives invalid data from any of the necessary modules, DTCs are set and the 4X4 control module may not allow Four-Wheel Drive (4WD) operation.

• DTC U0415 (Invalid Data Received from Anti-lock Brake System (ABS) Control Module) - When the 4X4 control module receives invalid HS-CAN  bus data or invalid wheel speed(s) from the ABS module for more than 5 seconds, this DTC is set.

This pinpoint test is intended to diagnose the following: 

• ABS module