Component Description For Sound System Amplifier Control Unit - GF82.62-P-5010FH

Model 238

Up To Model Year 2021

With Code 810 (Premium sound system)

except code 811 (High-End sound system)

Shown On Model 238.3

Fig 1: Sound System Amplifier Control Unit Components Location - Model 238 Up To Model Year 2021 With Code 810 Except Code 811 (Shown On Model 238.3)

Courtesy of MERCEDES-BENZ USA

Location

The sound system amplifier control unit is located in the trunk on the right behind the side paneling.

Tasks

Speed-dependent volume control (SDV)
Receive signals
Signal optimization and amplification
Transmitting signals

Speed-dependent volume control (SDV)

For the speed-dependent volume control (SDV), the sound system amplifier control unit evaluates the vehicle speed signal and the background noise recording via the driver-side hands-free system microphone (B25/20) and the front passenger-side hands-free system microphone (B25/21). The sound system amplifier control unit receives the signals via MOST from the head unit.

Receive signals

The input factors are read in via:

Direct lines
Media Oriented System Transport (MOST)
CAN (With Code B63 (Sporty engine sound))

Direct lines

The following signals are read in via a direct line:

Power supply via circuit 30t and circuit 31
Audio muting (mute function) from the HERMES control unit (N112/9) (with code 360 (HERMES UMTS) or with code 362 (HERMES LTE))
Electrical wake-up

Media Oriented System Transport (MOST)

The sound system amplifier control unit is a MOST subscriber and receives control and audio signals from the following components:

Head unit (A26/17)
Tuner unit (A90/4) (with code 522 (Audio 20 radio) and either code 536 (SIRIUS satellite radio) or code 537 (Digital radio (DAB))
TV tuner control unit (N143) (with code 865 (TV tuner))

CAN (With Code B63 (Sporty engine sound))

The sound system amplifier control unit receives control signals (e.g. engine rpm, engine load and vehicle speed) via the drive train CAN (CAN C1) from the ME-SFI control unit (N3/10)

Signal optimization and amplification

The sound system amplifier control unit has the following tasks when it is optimizing and amplifying the signals:

Optimize the input signals by digital signal processing and Surround Sound
Support of stereo and multichannel entertainment channels and announcement channels (e.g. for voice output in voice control system or navigation prompts)
Amplifying of the input signals and assignment of the output to the speakers
With code B63 (Sporty engine sound): Supplementing the sound panorama in the vehicle interior with simulated sound components in order to optimize the sound of the engine and exhaust system sound in the vehicle interior

Transmitting signals

The sound system amplifier control unit transmits signal tones and amplified, optimized audio signals to the following speakers via direct lines:

Left front door midrange speaker (H4/1) and left front door tweeter (H4/33)
Right front door midrange speaker (H4/2) and right front door tweeter (H4/34)
Left side paneling midrange speaker (H4/3) and left side paneling tweeter (H4/35)
Right side paneling midrange speaker (H4/4) and right side paneling tweeter (H4/36)
Center instrument panel speaker (H4/27)
Left front footwell woofer (H4/42)
Right front footwell woofer (H4/43)
Left rear midrange speaker for surround sound system (H4/62)
Right rear midrange speaker for surround sound system (H4/63)

Sound amplifier control unit wiring diagram

PE82.62-P-2101-97DCA