Speaker Output Function - GF82.62-P-4212FR

Model 257 (except 257.361) 

up to model year 2021 

Courtesy of MERCEDES-BENZ USA

Shown on model 257 

Function requirements for speaker output, general 

• Circuit 30t ON
• Transport mode not active

Speaker output, general 

The speaker system is actuated by one of the following components:

• Head unit (except code 810 (Sound system) and except code 811 (Advanced sound system) and except code B63 (Sporty engine sound))
• Engine sound control unit (with code B63 (Sporty engine sound) and except code 810 (Sound system) and except code 811 (Advanced sound system))
• Sound system amplifier control unit (with code 810 (Sound system))
• Advanced sound system amplifier control unit (with CODE 811 (Advanced Sound System))

A distinction is made between the following procedures:

• Speaker output in vehicles with code 811 (Sound system) 
• Speaker output in vehicles with code 810 (Sound system) 
• Speaker output in vehicles except code 810 (Sound system) and except code 811 (Advanced sound system) 

Model 257 (except 257.361)

up to model year 2021

with code 362 (HERMES communications module LTE)

The speaker actuation by the HERMES control unit (N112/9) is described elsewhere.

Speaker output in vehicles with code 811 (Sound system) 

The audio signals from the head unit or TV tuner control unit (with code 865 (TV tuner)) are routed via MOST to the Advanced sound system amplifier control unit, where they are finally amplified and output via the speakers using direct lines.

The head unit sends different variables for audio playback via MOST to the Advanced sound system amplifier control unit, such as volume and tone settings or signals for speed-dependent volume control (SDV [GAL]) including interference recording.

For vehicles with code B63 (Sporty engine sound), the Advanced Sound System amplifier control unit receives control signals (e.g. engine speed, engine load and vehicle speed) over the drive CAN from the ME-SFI [ME] control unit (gasoline engine) or from the CDI control unit (diesel engine), modulates derived synthesized sound signals over the audio source signals and outputs the composite signals through the speakers.

The Advanced sound system amplifier control unit emits the audio signals at the following speakers:

• Left front footwell woofer
• Right front footwell woofer
• Left front door sound system tweeter
• Right front door sound system tweeter
• Left rear door sound system tweeter
• Right rear door sound system tweeter
• Left front door sound system woofer/midrange speaker
• Right front door sound system woofer/midrange speaker
• Center instrument panel tweeter
• Center instrument panel midrange speaker
• Left rear door sound system midrange speaker
• Right rear door sound system midrange speaker
• Left front door midrange speaker
• Right front door midrange speaker
• Left rear surround sound system tweeter
• Left rear surround sound system midrange speaker
• Right rear surround sound system tweeter
• Right rear surround sound system midrange speaker
• Left front center overhead control panel midrange speaker (3D sound)
• Right front center overhead control panel midrange speaker (3D sound)
• Left center rear center midrange speaker (3D sound)
• Right center rear center midrange speaker (3D sound)
• Center midrange speaker at left center (3D sound)
• Center midrange speaker at right center (3D sound)

The signals for the rear woofer are sent by the Advanced sound system amplifier control unit to the rear woofer amplifier, which outputs the finally amplified signals via the speaker.

Speaker output in vehicles with code 810 (Sound system) 

The audio signals from the head unit or TV tuner control unit (with code 865 (TV tuner)) are routed via MOST to the sound system amplifier control unit, where they are finally amplified and output through the speakers using direct lines.

The head unit sends different variables for audio playback over MOST to the sound system amplifier control unit such as, e.g. volume and tone settings and signals for speed-dependent volume control (SDV [GAL]) including interference recording.

For vehicles with code B63 (Sporty engine sound), the sound system amplifier control unit receives control signals (e.g. engine speed, engine load and vehicle speed) over the drive CAN from the ME-SFI [ME] control unit (gasoline engine) or from the CDI control unit (diesel engine), modulates derived synthesized sound signals over the audio source signals and outputs the composite signals through the speakers.

The sound system amplifier control unit emits the audio signals at the following speakers:

• Left front door midrange speaker
• Right front door midrange speaker
• Left rear door midrange speaker
• Right rear door midrange speaker
• Center instrument panel speaker
• Left front door tweeter
• Right front door tweeter
• Left rear door tweeter
• Right rear door tweeter
• Left front footwell woofer
• Right front footwell woofer
• Left rear surround sound system midrange speaker
• Right rear surround sound system midrange speaker

Speaker output in vehicles except code 810 (Sound system) and except code 811 (Advanced sound system) 

On vehicles except code B63 (Sporty engine sound), the audio signals are output by the head unit via direct lines over the following speakers:

• Left front door midrange speaker
• Right front door midrange speaker
• Left rear door midrange speaker
• Right rear door midrange speaker
• Left front door tweeter
• Right front door tweeter
• Left footwell woofer (right-hand drive vehicles)
• Right footwell woofer (left-hand drive vehicles)

Model 257 (except 257.361)

up to model year 2021

with code 362 (HERMES communications module LTE)

The center instrument panel speaker is also installed and is actuated by the HERMES control unit.

On vehicles with code B63 (Sporty engine sound), the audio signals are forwarded by the head unit to the engine sound control unit. The engine sound control unit receives control signals (e.g. engine speed, engine load and vehicle speed) over the drive train CAN from the ME-SFI [ME] control unit (gasoline engine) or the CDI control unit (diesel engine) and derives synthesized sound signals from them. The engine sound control unit places the synthesized sound signals over the input signals of the head unit and sends the composite signals to the following speakers:

• Left front door midrange speaker
• Right front door midrange speaker
• Left rear door midrange speaker
• Right rear door midrange speaker
• Left front door tweeter
• Right front door tweeter
• Left footwell woofer (right-hand drive vehicles)
• Right footwell woofer (left-hand drive vehicles)

	Electrical function schematic for speaker system		PE82.62-P-2300-97XBA
	Overview of system components, telematics		GF82.85-P-9999FR