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GF82.62-P-3132LES Audio Tuner Control Unit, Component Description



GF82.62-P-3132LES Audio Tuner Control Unit, Component Description
- with CODE (810) Sound system


Component Identification:






Location
The audio tuner control unit is located on the left of the trunk.

Task
The audio tuner control unit manages all audio sources integrated in the vehicle (e.g. radio tuner) and processes and amplifies their audio signals. The audio tuner control unit also performs the following tasks:
^ Reading in of signals
^ Processing signals
^ Actuation of components

Reading in of signals
Signals are read in via the following connections:
^ Direct line
^ Media Oriented System Transport (MOST)

Direct line
The following signals are read in via direct lines:
- MUTE
- Wake-Up
- Antenna signals from the rear window antenna amplifier module (A2/12)
- Audio signals from the sound amplifier microphone (B25/6) (up to 31.5.09)
- Audio signals from the DVD player (A40/4) (model 221 with code (864) Rear entertainment system)

MOST
The following signals are read in via MOST:
- Audio signals from the following control units:
- COMAND controller unit (A40/3)
- UPCI [UHI] (Universal Portable Cell Phone Interface) control unit (N123/1) (up to 31.5.09 with code (386) Preinstallation for telephone "Cell phone", UPCI [UHI] system)
- Voice control system (VCS [SBS]) control unit (N41/3) (up to 31.5.09 with code (813) Voice control system (VCS [SBS]))
- Digital Audio Broadcasting control unit (N87/3) (with code (537) Digital radio)
- SDAR control unit (N87/5) (up to 31.5.09 with code (536) SIRIUS satellite radio)
- High definition tuner control unit (N87/8) (with code (517) HD radio)
- Emergency call system control unit (N123/4) (with code (359) TELE AID emergency call system)

Processing signals
The audio tuner control unit processes the following signals:
- Copy-protected audio signals
- DVD audio signals
- Radio signals
- Vehicle speed signal for speed-dependent volume control (SDV [GAL])
- Voice input from the sound amplifier microphone for dynamic range optimization (DRO) (up to 31.5.09)

Actuation of components
Components are actuated with the following connection:
^ Direct line

Direct line
The following components are actuated via direct lines:
- Model 216:
- Left door rear speaker (H4/3)
- Right door rear speaker (H4/4)
- Bass box speaker (H4/17)
- Center cockpit speaker (centerfill) (H4/27)
- Left rear surround speaker (H4/54)
- Right rear surround speaker (H4/57)
- Left door sound tweeter (H4/68)
- Right door sound tweeter (H4/69)
- Left door sound woofer and midrange speaker group (H4/72)
- Right door sound woofer and midrange speaker group (H4/73)

- Model 221:
- Left rear door speaker group (H4/3)
- Right rear door speaker group (H4/4)
- Bass box speaker
- Center cockpit speaker (centerfill)
- Left rear surround speaker
- Right rear surround speaker
- Left front door sound tweeter (H4/68)
- Right front door sound tweeter (H4/69)
- Left front door sound woofer and midrange speaker group (H4/72)
- Right front door sound woofer and midrange speaker group (H4/73)

Design
The following components are integrated in the audio tuner control unit:
- 2 radio receivers for reception of radio signals
- Decoder for processing audio signals in DVD mode (audio or video DVD)
- Integrated sound amplifier
- MOST interface
- Basic amplifier (audio signal output)

Diagnosis
The audio tuner control unit has its own fault memory. All faults that have occurred during operation are stored there.
On request, all the diagnostic data are forwarded to the COMAND controller unit via MOST.
The diagnostic data are forwarded via the central CAN (CAN A) to the central gateway control unit (N93) where they can be read out at the data link connector (X11/4).

The control units can be configured via diagnosis.
The following can be selected:
- Frequency bands
- Volume increase for incoming traffic messages TP volume
- Switch-off time, when circuit 15 Off