Steering Mounted Controls Assembly: Description and Operation
Multifunction Steering Wheel
Buttons are integrated in the steering wheel for easier operation of Infotainment, telephone and the navigation system. On vehicles with Tiptronic, rocker switches are also installed on the left and right.
The Multi-function Steering Wheel Control Module (J453) (under the right button) reads out the button information and transfers them over the LIN-Bus (single wire Bus) to the Steering Column Electronic Systems Control Module (J527). From the Steering Column Electronic Systems Control Module (J527) , the information is transferred to the individual components via the CAN bus (comfort) and the Data Bus On Board Diagnostic Interface (J533).
Fault finding is performed via "Guided Fault Finding" using the Vehicle Diagnostic Tester.