Steering Mounted Controls Assembly: Description and Operation

Multifunction Steering Wheel

=> [ Multifunction Steering Wheel ]

=> [ Multifunction Buttons ]

=> [ Steering Column Control Module ]

Multifunction Steering Wheel

CAUTION!
• Disconnect battery ground wire before working on electrical system.

• On vehicles with Telematics, activate Telephone/Telematics Control Module service mode before disconnecting Battery (A). Refer to => [ Telematics Service Mode, Activating/Deactivating ] Testing and Inspection.

If the battery is reconnected, follow the procedure for disconnecting and connecting the battery. Deactivate Telephone/Telematics Control Module ( J526) service mode. Refer to => [ Telematics Service Mode, Activating/Deactivating ] Testing and Inspection.

Six function buttons are integrated in the steering wheel to facilitate radio and telephone operation when driving. In addition, multifunction steering wheel is heated electrically.

The electronics installed in the steering wheel converts button signals to the LIN data bus (single wire bus) and dims function buttons. On vehicles with automatic transmission, 2 additional switches can be installed for Tiptronic. The electronics in the steering wheel cannot be replaced individually. In case of faulty electronics, the entire steering wheel must be replaced.

The multifunction steering wheel is part of the complete "Steering column switch module" (SMLS) system and delivers data via the LIN data bus to the Steering Column Electronic Systems Control Module.

Fault finding is performed. Refer to Guided Fault Finding Vehicle diagnosis, testing and information system VAS 5051.

Repair to CAN bus lines. Refer to => Service and Repair

Multifunction Buttons

Two versions of the multifunction steering wheel are used.

Multifunction steering wheel with two blocks of buttons





Removing and installing multifunction buttons, Refer to => [ Multifunction Steering Wheel ] Multifunction Steering Wheel.

Multifunction steering wheel with roller buttons





Removing and installing multifunction buttons, Refer to => [ Multifunction Steering Wheel ] Multifunction Steering Wheel.

Steering Column Control Module

CAUTION!
• Disconnect battery ground wire before working on electrical system.

• On vehicles with Telematics, activate Telephone/Telematics Control Module service mode before disconnecting Battery (A). Refer to => [ Telematics Service Mode, Activating/Deactivating ] Testing and Inspection.

If the battery is reconnected, follow the procedure for disconnecting and connecting the battery. Deactivate Telephone/Telematics Control Module ( J526) service mode. Refer to => [ Telematics Service Mode, Activating/Deactivating ] Testing and Inspection.

The Steering Column Electronic Systems Control Module (J527) is a part of the "steering column switch module ". The "steering column switch module" consists of:

• Left and right steering column switch

• airbag spiral spring

• Steering Angle Sensor (G85)

• Ignition/Starter Switch (D)

• Steering Column Electronic Systems Control Module ( J527)

The Steering Column Electronic Systems Control Module (J527) exchanges data between vehicle control modules ( Vehicle Electrical System Control Module (J519)) and steering column modules (steering column switch) and steering wheel modules (e.g. airbag).

In addition, multifunction steering wheel button signals are process and relayed via CAN BUS.

Fault finding is performed via Guided Fault Finding Vehicle diagnosis, testing and information system VAS 5051.

Repair to CAN bus lines. Refer to => Service and Repair