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GF82.85-P-2030CWA Audio Mode, Function



GF82.85-P-2030CWA Audio Mode, Function
- with CODE (512) COMAND APS with DVD changer
- Radio, CD, DVD


Function requirements
^ Status "circuit 30 ON" or "circuit 15R ON"
^ The Cockpit Management and Data System (COMAND) is authorized and working correctly.
^ No fault in antenna system (radio function)
^ Data DVD/CD inserted
^ Integrated hard drive working correctly

If "circuit 15R OFF", the COMAND controller unit (A40/3) activates the Media Oriented System Transport (MOST) users when it is switched on.

The following audio functions can be selected using the 'Audio' menu item
^ Radio (AM/FM)
^ Music server
^ Weather band (for vehicles with code (494) USA version)
^ DVD/CD audio as well as MP3 (on DVD/CD)
^ DVD/CD video (for vehicles except code (494) USA version)
^ Digital Audio Broadcasting (Digital Radio) (DAB) (with code (537) Digital radio)
^ Satellite Digital Audio Radio (satellite radio) (SDAR) (with code (536) SIRIUS satellite radio)
^ External analog audio source via the AUX jack in the glove compartment

Operating instructions
The audio functions can be controlled, or selected and set, using the following components:
^ Left multifunction steering wheel button group (S110)
^ Group of buttons on right of multifunction steering wheel (S111)
^ Audio/COMAND control panel (A40/9)
^ Control fields on the COMAND controller unit

General information on radio mode (AM/FM)
The radio tuner for the AM/FM range is integrated into the COMAND controller unit. The radio tuner comes with the following functions:
^ AM tuner (MW, LW, SW)
^ Traffic Announcement (TA), evaluation of traffic information radio channel via the Traffic Message Channel (TMC) for dynamic route guidance with navigation (for vehicles except code (494) USA version)
^ Radio Data System (RDS) (for vehicles except code (494) USA version)
^ Radio Broadcast Data System (RBDS), weather band (for vehicles with code (494) USA version)
^ FM dual tuner with phase diversity

Function sequence for radio reception (AM/FM)
The antennas in the rear window receive high frequency (HF) signals for ultra-short wave (FM) and medium wave (MW). Modulated onto these HF signals are music, voice or data signals. The FM, AM and central locking antenna amplifier (A2/18) and the antenna amplifier for the rear window FM antenna (A2/19) (204.0) or the FM, AM and central locking antenna amplifier and the rear window antenna amplifier 1 (A2/71) (204.2) filter the frequencies of the radio frequency bands out of the received HF signals and amplify them. The amplified signals are then sent over the coaxial lines (FM, AM) to the integrated radio tuner of the COMAND controller unit. The radio tuners demodulate the HF signals, in other words they separate the useful information (audible frequencies) from the carrier signal (inaudible).

The audio signals on vehicles with code (810) Sound system are sent by the COMAND controller unit over MOST to the sound system amplifier control unit (N40/3) where they are then finally amplified.

Vehicles except code (494) USA version also receive TA and TMC messages over the HF signals. Vehicles with code (494) USA version also receive weather information over the HF signals.

Audio output (AM/FM)
The audio output of the signals amplified and processed by the sound system amplifier control unit takes place over discrete lines through the following speakers:
^ Left front door speaker (H4/1)
^ Right front door speaker (H4/2)
^ Left rear door speaker (H4/3)
^ Right rear door speaker (H4/4)
^ Center instrument panel speaker (H4/27)
^ Bass speaker (H4/29)
^ Left rear surround speaker (H4/54)
^ Right rear surround speaker (H4/57)

On model designation 204.0 with code (810) Sound system, the right rear surround speaker is integrated into the bass speaker (H4/29).

On model designation 204.2 with code (810) Sound system, the left rear surround speaker (H4/54) is installed in the left D-pillar and the right rear surround speaker (H4/57) in the right D-pillar. The bass speaker (H4/29) is installed in the left load compartment.

On vehicles except code (810) Sound system, the audio output takes place directly over discrete lines via the COMAND controller unit through the following speakers:
^ Left front door speaker
^ Right front door speaker
^ Left rear door speaker
^ Right rear door speaker
^ Center instrument panel speaker

General Radio Data System (RDS) or Radio Broadcast Data System (RBDS) function
In addition to the radio program, many radio stations (FM) also broadcast additional digital information such as station name and traffic message channel recognition. This information is evaluated by the COMAND controller unit and shown on the Audio/COMAND display (A40/8), when the following preconditions are complied with:
^ An RDS or RBDS station is set.
^ The RDS or RBDS function has been activated.

FM antenna diversity, function
If reception problems occur while driving, the COMAND controller unit tries to receive the selected station on an alternative frequency with the aid of the radio tuner, and then tries to switch over accordingly if reception improves. A switchover is made depending on reception quality between the rear window FM antennas. The function runs automatically.

Function sequence for DVD/CD audio and video
Integrated into the COMAND controller unit is a 6-disk DVD changer with a single-slot. This enables audio CDs or audio DVDs (including in MP3 format) as well as video CDs or video DVDs to be played. User guidance for controlling DVD/CD functionality and displaying supplemental information is carried out via the Audio/ COMAND display.

The DVD/CD menu and the Title menu, which are stored on the inserted DVD/CD, and the DVD/CD slots that are occupied, are shown on the Audio/COMAND display. Slots "1" to "6" are numbered consecutively. For this reason, the function scope and menu display are dependent on each respective medium. In the event that one of the two menus is missing on the DVD/CD, the Audio/COMAND display on the COMAND controller unit provides the corresponding soft key is highlighted with a gray background.

For vehicles with code (810) Sound system, data exchange takes place between the COMAND controller unit and the sound system amplifier control unit over MOST.
The audio signal output then takes place over discrete lines at the following speakers:
^ Left front door speaker
^ Right front door speaker
^ Left rear door speaker
^ Right rear door speaker
^ Center instrument panel speaker
^ Bass speaker
^ Left rear surround speaker
^ Right rear surround speaker

On model designation 204.0 with code (810) Sound system, the right rear surround speaker is integrated into the bass speaker (H4/29).

On model designation 204.2 with code (810) Sound system, the left rear surround speaker (H4/54) is installed in the left D-pillar and the right rear surround speaker (H4/57) in the right D-pillar. The bass speaker (H4/29) is installed in the left load compartment.

On vehicles except code (810) Sound system, the audio output takes place directly over discrete lines via the COMAND controller unit through the following speakers:
^ Left front door speaker
^ Right front door speaker
^ Left rear door speaker
^ Right rear door speaker
^ Center instrument panel speaker

General music server
The integrated hard drive in the COMAND controller unit enables files (in MP3 format) to be stored from the CD via the PCMCIA interface and then called up as and when required.