Rear Differential Clutch Control Module

The rear differential clutch control module is fitted on the housing. The hydraulic pressure is built up by the differential clutch pump, and is controlled by the rear differential clutch control module via the rear drive clutch solenoid valve. Utilizing information on the serial data bus, the rear differential clutch control module calculates the drive torque distribution between front and rear axles as well as the distribution between the rear wheels for vehicles with limited slip differential clutch. The rear differential clutch control module is connected to the vehicle's high speed communication bus. The serial data messages are used to determine the operating/driving conditions for the vehicle and how much drive torque should be transferred to the rear wheels. Since the rear differential clutch control module and the rear drive clutch solenoid valve are calibrated as a matched set, they must be replaced together without exception.

The rear differential clutch control module is constantly monitoring for bus communication, inputs, outputs, certain mechanical faults and internal control module faults. If relevant control module functions are missing or other mechanical or electrical faults are recognized, diagnostic trouble codes are generated.

• Internal signals

  The control module has a monitoring for internal control module faults.

• Input signals

  The control module has an input for an internal temperature sensor. The temperature sensor is fitted on the rear differential control module circuit board and is monitored for electrical faults. The temperature sensor is also used by the rear differential control module to calculate the current fluid and disc pack temperature in the differential clutch.

• Output signals

  The rear differential clutch control module has outputs for the rear drive clutch solenoid valve and the rear differential clutch solenoid valve for the limited slip differential clutch (if equipped) as well as for the differential clutch pump. These are all monitored for electrical faults.

• Mechanical functions

  The control module can diagnose clogged pressure control valves and leaking check valves.