Normal Operation

The All-Wheel Drive (AWD) system continuously monitors vehicle conditions and automatically adjusts the torque distribution between the front and rear wheels. During normal operation, most of the torque is sent to the front wheels. If wheel slip between the front and rear wheels is detected or the vehicle is under heavy acceleration, the AWD  system increases torque to the rear wheels.

If the spare tire is installed, the AWD  system may disable automatically and enter Front Wheel Drive (FWD) only mode to protect driveline components. This condition may be indicated by an AWD  OFF message in the message center.

If there is an AWD  OFF message in the message center from using the spare tire, this indicator should turn off after reinstalling the repaired or replaced normal road tire and driving a short distance. It is recommended to reinstall the repaired or replaced road tire as soon as possible. Major dissimilar tire sizes between the front and rear axles could cause the AWD  system to stop functioning and default to FWD  or damage the AWD  system.

• DTC P1635 (Tire/Axle Out of Acceptable Range) - When the 4X4 control module detects inappropriate mini spare or road wheels/tires (greater than 7% across the front and rear axle or 14% at one wheel) installed, this DTC is set.

This pinpoint test is intended to diagnose the following: 

• Wheels/tires
• Wheel speed sensors
• ABS module
• 4X4 control module