Control Unit: Description and Operation

Control module, all-wheel drive (724)

Location

Control module, all-wheel drive (724)

Main function

The function of the control module is to regulate the engagement of the differential clutch, and on cars with limited slip differential clutch its engagement too.

Type

Has a microprocessor, see Control module, general description. The software in the control module can be updated with SPS.





Electrical connections

K12





K4





Diagram





Function

The XWD control module, abbreviated to RDCM, is connected to the vehicle's P-bus. Its bus messages are used to determine the operating/driving conditions for the vehicle, and accordingly how much drive torque should be transferred to the rear wheels. The control module and control valve are calibrated together, and they must be replaced together without exception.