9-3 FWD (9440) L4-2.0L Turbo (B207R) (2009)
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.