04 Transmission: Function

If a wheel speed sensor on the front axle identifies that a wheel is spinning (when cornering, the inner wheel), the signal is sent across the CAN-Bus to J647 Axle Differential Lock Control Module. J647 increases the speed of the Haldex Clutch Pump -V181-, which applies variable pressure to the working piston. The working piston compresses the clutch pack.

The amount of pressure also affects the transfer of torque (from the spinning wheel to the driven outer wheel). This allows a torque of between 0 and 100% to be transferred. The torque acting on the inner wheel is reduced and directed to the driven outer wheel. The difference in speed between the inner wheel and the outer wheel remains the same.