Audio system function - GF82.60-P-0004CW

WARNING: This page is about a different car, the 2011 Mercedes-Benz C300, 2010 Mercedes-Benz C300, 2009 Mercedes-Benz C300, and 2008 Mercedes-Benz C300. However, it is still accessible from the selected car via links, so may be relevant.

MODEL 204.0 /2

with CODE (523) MB Audio 20 radio

up to Model Year 2008

MODEL 204.0

with CODE (494) USA version

up to Model Year 2008

MODEL 204.0 /2

with CODE (510) Audio 20 with CD changer

up to Model Year 2008

Function requirements

- Status "circuit 30 ON" or "circuit 15R ON"

- The radio is authorized and in perfect working order

General

The radio (A2) is the central operating unit for the entertainment and communication systems integrated into the vehicle. The audio system is made up of the following component functions:

- Audio mode

- Volume and tone settings

- Telephone mode

The displays and menu displays for the Audio/COMAND display (A40/8) are generated in the radio.

The radio, except code (523) MB Audio 20 radio, communicates with the following control units over the Media Oriented System Transport (MOST):

- Digital Audio Broadcasting control unit (N87/3) for vehicles with code (537) Digital radio

- Satellite digital audio radio (SDAR) control unit (N87/5) for vehicles with code (536) SIRIUS satellite radio

- Sound system amplifier control unit (N40/3) for vehicles with code (810) Sound system

The radio, except code (523) MB Audio 20 radio, acts as a gateway. It routes the signals from the interior CAN to the telematics CAN and the MOST components and forms the communications interface (master control unit).

For vehicles with code (523) MB Audio 20 radio a MOST is not used.

Operating instruction

The system can be operated using the following controls:

- Control buttons on the radio

- Audio/COMAND control panel (A40/9)

- Left multifunction steering wheel button group (S110) and right multifunction steering wheel button group (S111)

The control signals of the left multifunction steering wheel button group and the right multifunction steering wheel button group are routed here via the steering LIN to the control unit for the steering column module (N80), and then on over the chassis CAN to the instrument cluster (A1) and then from there to the radio via the interior CAN.

Diagnosis

The radio is the diagnosis gateway for all MOST users. Diagnosis is performed using the Keyword 2000 protocol via the diagnostic CAN to the front SAM control unit with fuse and relay module (N10/1) and from there via the interior CAN to the COMAND controller unit.