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Home >> Mercedes Benz >> 2004 >> C 320 CL (203.764) V6-3.2L (112.946) >> Repair and Diagnosis >> Accessories and Optional Equipment >> Radio, Stereo, and Compact Disc >> Description and Operation >> GF82.60-P-2003FAC Volume/Tone Adjustments, Function

GF82.60-P-2003FAC Volume/Tone Adjustments, Function




GF82.60-P-2003FAC Volume/Tone Adjustments, Function

MODEL 203.7
- with CODE (527) COMAND APS with single DVD drive (with navigation)
MODEL 203.7 as of model year 09/YoM 08 model refinement package

Function requirements
- Status "Circuit 30 ON" or "Circuit 15R ON"
- Cockpit Management and Data System (COMAND) authorized and working correctly
- Audio source in operation

General
All sound settings are made on the COMAND operating, display and controller unit (A40/3) or on the multifunction steering wheel (MFL). All sound settings are made on the COMAND operating, display and controller unit.

The signal processing required for the volume and sound settings is carried out by the COMAND operating, display and controller unit, or in vehicles with code (810) Sound system, the amplifier for sound system (N40/3). The amplifier for sound system receives the signals via Media Oriented System Transport (MOST) from the COMAND operating, display and controller unit.

On vehicles with code (810) Sound system, the audio signals are output by the COMAND operating, display and controller unit via the MOST to the amplifier for the sound system and from there, over direct lines, to the following speakers:
- Left front door speaker (H4/1)
- Right front door speaker (H4/2)
- Left rear door speaker (H4/5)
- Right rear door speaker (H4/6)
- Left front door speaker, mirror triangle (H4/23)
- Right front door speaker, mirror triangle (H4/24)
- Center cockpit speaker (centerfill) (H4/27)
- Subwoofer speaker (H4/29)
- Left rear surround speaker (H4/54)
- Right rear surround speaker (H4/57)

On vehicles except code (810) Sound system, the audio signals are output by the COMAND operating, display and controller unit to the following speakers via direct lines:
- Left front door speaker
- Right front door speaker
- Left rear door speaker
- Right rear door speaker
- Left front door speaker, mirror triangle
- Right front door speaker, mirror triangle

It is necessary to differentiate between audio sources and service sources:
Audio sources are:
- Radio tuner
- DVD drive in audio CD mode

Service sources are:
- Traffic announcement
- Telephone system, with code (386) Mobile phone

The volume and sound setting function comprises the following subfunctions:
- Function sequence for manual volume setting on the COMAND operating, display and controller unit
- Function sequence for manual volume setting on the multifunction steering wheel
- Function sequence for speed-dependent volume control (SDV [GAL])
- Function sequence for muting (mute)
- Function sequence for sound setting

Operating instructions
The volume can be adjusted with the following components:
- With the left multifunction steering wheel button group (S110) and the right multifunction steering wheel button group (S111) on the multifunction steering wheel
- With the control buttons and the combination push and rotary button of the COMAND operating, display and controller unit

The sound settings can be made with the following components:
- With the control buttons and the combination push and rotary button of the COMAND operating, display and controller unit

Function sequence for manual volume setting on the COMAND operating, display and controller unit
The volume is adjusted on the combination push and rotary button of the COMAND operating, display and controller unit for the audio source that is active in each case. In addition, it can be set separately in all audio and service areas (telephone, traffic information radio channel). Via the "TP Vol." softkey assignment, it is possible to increase or decrease the volume for the traffic information.

Function sequence for manual volume setting on the multifunction steering wheel
The volume is regulated for the audio source that is active in each case. The control signals of the left multifunction steering wheel button group and the right multifunction steering wheel button group on the multifunction steering wheel are transmitted to the COMAND operating, display and controller unit in the following way:
- Steering LIN
- Steering column tube module (N80)
- Interior CAN

Function sequence for speed-dependent volume control
The speed-dependent volume control can be used to adapt the volume to the noise level in the vehicle interior. In this case, the vehicle speed signal is used as the reference value. The vehicle speed signal is forwarded to the COMAND operating, display and controller unit in the following way:
- Instrument cluster (A1)
- Interior CAN

The speed-dependent volume control runs automatically. After evaluating the relationship indicator, the audio output is matched to the noise level in the vehicle interior. Depending on the vehicle speed signal, the COMAND operating, display and controller unit raises or lowers the output level of the audio signals.

In vehicles with code (810) Sound system, dynamic range optimization (DRO) is used in addition, which is implemented by the sound amplifier microphone (B25/6) and the amplifier for sound system.

Function sequence for muting (mute)
It is necessary to differentiate between the following cases:
- Function sequence for manual muting
- Function sequence for automatic muting, with code (386) Mobile phone

Function sequence for manual muting
If the user presses the "Mute" function key on the COMAND operating, display and controller unit, the audio source currently being listened to is muted. The integrated DVD drive changes to a pause status, if it is in audio mode. The signal is processed internally.

Function sequence for automatic muting, with code (386) Mobile phone
When accepting an incoming telephone call, the COMAND operating, display and controller unit switches to telephone mode and mutes the audio source.

Function sequence for sound setting
The COMAND operating, display and controller unit allows manual sound settings (bass, treble, balance, and fader) for each audio source. The "AUDIO" function status can be called up from every other function state, except "AUTO-ON".
The bass is shown on the display of the COMAND operating, display and controller unit as the 1st sound setting called up. By pressing the "AUDIO" function key repeatedly, the other setting options for treble, balance (left/right), fader (front/rear), volume increase and traffic announcements can be called up. The messages of the AUDIO function status are output in the display field. The tone control only relates to the active system function status.

The sound settings (balance, fader) can be performed by actuating the main function buttons for sound distribution in the left control panel. If the tone emphasis is changed (balance, fader) the volume relationship between the individual speakers changes relative to each other.
The "Reset" function enables predefined sound settings (bass and treble) to be reset to their neutral position.

In vehicles with code (810) Sound system, the "Sound" menu is available additionally for extended sound settings.





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