Four Wheel Drive (4WD) Systems

Four Wheel Drive (4WD) Systems

The All-Wheel Drive (AWD) system consists of the following:

- PCM

- Power Transfer Unit (PTU)

- Rear driveshaft

- AWD (All-Wheel Drive) relay module

- Rear axle with Active Torque Coupling (ATC) device

Torque from the engine is transferred through the transaxle to the PTU (Power Transfer Unit). The PTU (Power Transfer Unit) is a mechanical device attached to the transaxle. This torque is transferred through the driveshaft to the rear axle, which drives the rear halfshafts. The AWD (All-Wheel Drive) system is always active and requires no driver input.

The AWD (All-Wheel Drive) 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 if the vehicle is under acceleration (high throttle position), the AWD (All-Wheel Drive) system increases torque to the rear wheels to prevent or control wheel slip. The PCM controls the rear axle coupling to apply the torque generated from the PTU (Power Transfer Unit) to the rear wheels when required.

NOTE: The ATC solenoid is not repairable. If a new component is required, the ATC solenoid and rear axle are installed as an assembly.

For concerns with the PTU, refer to Transfer Case.