Shown on model 218.3 as of 01.09.2014 |
N40/3 | Sound system amplifier control unit |
P82.62-4129-05
Shown on model 218.3 up to 31.08.2014 |
N40/3 | Sound system amplifier control unit |
P82.62-3837-05
Shown on model 218.9 as of 01.09.2014 |
N40/3 | Sound system amplifier control unit |
P82.62-4128-05
Shown on model 218.9 up to 31.08.2014 |
N40/3 | Sound system amplifier control unit |
P82.62-3838-05
Location
The sound system amplifier control unit is located in the trunk behind the cover on a bracket, on model 218.3 under the rear shelf and on model 218.9 on the left sidewall in front of the wheel arch.
Tasks
Receive signals
Decoding signals
Amplification, support and processing of signals
Transmitting signals
Receive signals
The input signals are read in via the following connections:
Media Oriented System Transport (MOST)
Direct lines
Media Oriented System Transport (MOST)
The sound system amplifier control unit is a MOST participant and receives audio signals from the following components:
Audio equipment
Tuner unit (A90/4) (with code 536 (SIRIUS satellite radio), with code 537 (Digital radio) or with code 865 (TV tuner), as of 01.09.2014)
Satellite digital audio radio (SDAR) control unit (N87/5) (with code 536 (SIRIUS satellite radio), up to 31.08.2014)
Digital Audio Broadcasting control unit (N87/3) (with code 537 (Digital radio), up to 31.08.2014)
Digital TV tuner (A90/3) (with code 865 (TV tuner), up to 31.08.2014)
Media interface control unit (N125/1) (with code 518 (Media Interface), up to 31.08.2014)
Direct lines
Power supply via circuit 31 and circuit 30 via one direct line each
Muting of audio sources (with code 348 (Emergency call/Assist system), with code 350 (eCall Europe emergency call system) or with code 351 (Emergency call system (HERMES))
Optical and electrical wake-up
Signals from sound system microphone (B25/6)
Decoding signals
Decoding copy-protected audio signals on basis of latest Digital Signal Processing (DSP) technology.
DSP means that for the audio range, audio tracks are processed using mathematical algorithms with the objective of improving the acoustic sound characteristics.
Amplification, support and processing of signals
Decoding of copy-protected audio signals based on Digital Signal Processing (DSP) technology
Supporting surround sound (Bang&Olufsen)
Supporting 2 stereo entertainment channels and 3 announcement channels (e.g. for voice output of navigation instructions, etc.)
Amplifying decoded audio signals
Evaluation of signals for optimized speed-dependent volume control (SDV)
Transmitting signals
The sound system amplifier control unit emits the audio signals via the following connections:
5x line out (+ and –) for the rear woofer amplifier (N40/9) up to 31.08.2014
Remote for rear woofer amplifier (up to 31.08.2014)
Left rear door speaker (H4/3) (as of 01.09.2014)
Right rear door speaker (H4/4) (as of 01.09.2014)
Rear woofer (H4/38) (as of 01.09.2014)
Left front door sound system woofer (H4/64) (as of 01.09.2014)
Right front door sound system woofer (H4/65) (as of 01.09.2014)
Left front door speaker (H4/1)
Right front door speaker (H4/2)
Left front door speaker, mirror triangle (H4/23)
Right front door speaker, mirror triangle (H4/24)
Center instrument panel speaker (H4/27)
Left rear surround speaker (H4/54)
Right rear surround speaker (H4/57)
Left rear door sound system tweeter (H4/70)
Right rear door sound system tweeter (H4/71)
The sound system amplifier control unit controls the illumination of the following speakers:
Left front door speaker, mirror triangle
Right front door speaker, mirror triangle
Actuation takes place via the rear woofer amplifier up to 31.08.2014 and via direct lines as of 01.09.2014.
Body
On vehicles as of 01.09.2014 the rear woofer amplifier functions are integrated into the sound system amplifier control unit, and the rear woofer amplifier is no longer installed.
Function
The sound system amplifier control unit is actuated via the audio equipment. The audio equipment also provides all of the menus for user guidance.
For optimized speed-dependent volume control (SDV), the sound system amplifier control unit evaluates the following signals:
Vehicle speed signal from the audio equipment, via MOST
Signals from the sound system microphone, via a direct line