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

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

MODEL 203.7
- with CODE (523) MB Audio 20 radio
MODEL 203.7 as of model year 09/YoM 08 model refinement package

Function requirements
- Status "Circuit 30 ON" or "Circuit 15R ON"
- The radio is authorized and in perfect working order
- Audio source in operation

General
All volume settings are made on the control panel of the radio (A2) or on the multifunction steering wheel (MFL). All sound settings are made on the control panel of the radio. The signal processing required for the volume and sound settings is carried out by the radio, 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 radio.

In vehicles with code (810) Sound system, the audio signals are output by the radio via the MOST to the amplifier for sound system (N40/3) and from there to the following speakers via direct lines:
- 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)

In vehicles except code (810) Sound system, the audio signals are output by the radio 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
- CD drive

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 radio
- 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 radio

The sound settings can be made with the following components:
- With the control buttons and the combination push and rotary button of the radio

Function sequence for manual volume setting on the radio
The volume is regulated on the combination push and rotary button of the radio 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 radio 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 speed signal is transferred to the radio over the following path:
- Instrument cluster (A1)
- Interior CAN
- Radio

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 radio 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 function key "Mute" on the radio, the audio source currently being listened to is muted and the CD disk drive changes to a pause status. The signal is processed internally.

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

Function sequence for sound setting
The radio permits 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 display on the radio shows the bass as the 1st called up sound setting. 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.