4WD Transfer Case
The 4WD ECU first analyzes sensor signals regarding the 4WD wheel speed, accelerator, and steering angle and distributes power to the front and rear wheels by controlling the multi-layered clutch depending on the road conditions and driving conditions.
- Motor Pump: The 4WD ECM rotates the motor pump (actuator) installed in the electric coupling and creates oil pressure. It then presses the multi-layered clutch with oil pressure to control the 4WD system and deliver the torque to the rear wheels. The torque values can vary depending on the amount of pressure to the clutch.
- Pressure Sensor: The 4WD ECM controls the motor pump based on the current pressure value it receives from the pressure sensor installed in the coupling. The 4WD ECU uses the information to reach the target oil pressure level that is needed to create enough torque to the rear wheels.