A8L V8-4.2L (BFM) (2004)
Steering Mounted Controls Assembly: Description and Operation
Multi-Function Steering Wheel
Buttons are integrated in the steering wheel to facilitate operating the radio system, telephone and navigation announcement 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, 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 Diagnosis, Testing and Information System (VAS5051).