Speaker Output Function - GF82.62-P-4212LFM
Model 217, 222 as of model year 2018
Shown on model 222
Show on model 217
Function requirements for speaker output, general
- Circuit 30t ON
- Transport mode not active
Speaker output, general
A distinction is made between the following procedures:
- Speaker output in vehicles with code 811 (Advanced sound system)
- Speaker output in vehicles with code 810 (Sound system)
- Speaker output in vehicles except CODE 811 (Advanced sound system) and except CODE 810 (Sound system)
- Speaker actuation for front voice output
- Active engine noise compensation (AMGK) (with code 97B (Engine noise reduction via speakers))
- Acoustic operation feedback
Speaker output in vehicles with code 811 (Advanced sound system)
The audio signals are routed from the head unit, from the Rear Seat Entertainment system controller unit (with code 864 (Rear Seat Entertainment system)) or from the TV tuner control unit (with code 865 (TV tuner)) over the Media Oriented System Transport (MOST) to the Advanced sound system amplifier control unit, where they undergo final amplification, and where they are emitted through direct lines at the following speakers:
- Left footwell woofer
- Right footwell woofer
- Left front door tweeter
- Right front door tweeter
- Left rear door tweeter (model 222) or left rear sidewall lining tweeter (model 217)
- Right rear door tweeter (model 222) or right rear sidewall lining tweeter (model 217)
- Left front door midrange speaker
- Right front door midrange speaker
- Center instrument panel tweeter
- Center instrument panel midrange speaker
- Left rear door midrange speaker (model 222) or left rear sidewall lining midrange speaker (model 217)
- Right rear door midrange speaker (model 222) or right rear sidewall lining midrange speaker (model 217)
- Left front door woofer/midrange speaker
- Right front door woofer/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
- Center console tweeter (model 217)
- Center console mid-range speaker (model 217)
- Left rear door woofer/midrange speaker (model 222) or left rear side wall trim woofer/midrange speaker (model 217)
- Right rear door woofer/midrange speaker (model 222) or right rear side wall trim woofer/midrange speaker (model 217)
- Center front left overhead control panel mid-range speaker (3D sound) (except model 217.4)
- Center front right overhead control panel mid-range speaker (3D sound) (except model 217.4)
- Center left rear center midrange speaker (3D sound) (except model 217.4)
- Center right rear center midrange speaker (3D sound) (except model 217.4)
- Left center headliner midrange speaker (3D sound) (model 222)
- Right center headliner midrange speaker (3D sound) (model 222)
The Advanced sound system amplifier control unit forwards the audio signals for the subwoofer to the subwoofer amplifier.
Model 217, 222
as of model year 2018
with code 360 (HERMES UMTS)
Model 217, 222
as of model year 2018
with code 362 (HERMES LTE)
In telematics services with voice connection (e.g. emergency call), the center instrument panel midrange speaker is used for voice output and actuated via direct lines by the HERMES control unit.
During actuation of the speaker system, the volume is adapted to the noise level in the vehicle interior. For volume adjustment, the head unit transfers the vehicle speed signal and the signals of the driver hands-
free system microphone and front passenger hands-free system microphone (interference recording) via the Media Oriented System Transport (MOST) to the Advanced sound system amplifier control unit.
Model 222
as of model year 2018
with code 811 (Advanced sound system)
During operation, the left front door sound system tweeter and the right front door sound system tweeter are extended by the actuator motor actuated by the respective left front door control unit (N69/1) or right front door control unit (N69/2), and are illuminated when the ambiance illumination is switched on. Upon parking the vehicle, the left front door tweeter and right front door tweeter are retracted again and the lights are switched off.
Speaker output in vehicles with code 810 (Sound system)
The audio signals are routed from the head unit, from the Rear Seat Entertainment system controller unit (with code 864 (Rear Seat Entertainment system)) or from the TV tuner control unit (with code 865 (TV tuner)) over the Media Oriented System Transport (MOST) to the sound system amplifier control unit, where they undergo final amplification, and where they are emitted through direct lines at the following speakers:
- Center instrument panel speaker
- Left footwell woofer
- Right footwell woofer
- Left rear surround sound system midrange speaker
- Right rear surround sound system midrange speaker
- Left front door tweeter
- Right front door tweeter
- Left rear door tweeter (model 222) or left rear sidewall lining tweeter (model 217)
- Right rear door tweeter (model 222) or right rear sidewall lining tweeter (model 217)
- Left front door midrange speaker
- Right front door midrange speaker
- Left rear door midrange speaker (model 222) or left rear sidewall lining midrange speaker (model 217)
- Right rear door midrange speaker (model 222) or right rear sidewall lining midrange speaker (model 217)
Model 217, 222
as of model year 2018
with code 360 (HERMES UMTS)
Model 217, 222
as of model year 2018
with code 362 (HERMES LTE)
With telematics services with a voice connection (e.g. emergency call), the center instrument panel speaker is used for voice output and actuated via direct lines by the HERMES control unit.
During actuation of the speaker system, the volume is adapted to the noise level in the vehicle interior. For volume adjustment, the head unit transfers the vehicle speed signal and the signals of the driver hands-free system microphone and front passenger hands-free system microphone (interference recording) via the Media Oriented System Transport (MOST) to the sound system amplifier control unit.
Speaker output in vehicles except CODE 811 (Advanced sound system) and except CODE 810 (Sound system)
The audio signals are output by the head unit via direct lines over the following speakers:
- Left footwell woofer
- Right footwell woofer
- Left front door tweeter
- Right front door tweeter
- Left rear door tweeter (model 222) or left rear sidewall lining tweeter (model 217)
- Right rear door tweeter (model 222) or right rear sidewall lining tweeter (model 217)
- Left front door midrange speaker
- Right front door midrange speaker
- Left rear door midrange speaker (model 222) or left rear sidewall lining midrange speaker (model 217)
- Right rear door midrange speaker (model 222) or right rear sidewall lining midrange speaker (model 217)
Model 217, 222
as of model year 2018
with code 360 (HERMES UMTS)
Model 217, 222
as of model year 2018
with code 362 (HERMES LTE)
The center instrument panel speaker that is used for voice output and actuated by the HERMES control unit for telematics services with voice link (e.g. emergency call) is additionally installed.
Speaker actuation for front voice output
In the case of front voice output (e.g. as part of telephony, navigation, emergency call or the voice control system), the audio quality is optimized for the front passenger compartment area in the vehicle by the head unit. In vehicles with code 810 (Sound system), optimization is undertaken by the sound system amplifier control unit, and by the Advanced sound system amplifier control unit with code 811 (Advanced sound system).
Additional function requirements for in-car communication (model 222 with code 810 (Sound system) or with code 811 (Advanced sound system))
- Circuit 15 ON
- In-car communication is activated on the head unit.
- In-car communication can be activated at medium volume.
- Voice control system (VCS [SBS]) is not active.
- The vehicle's windows and doors are closed.
In-car communication (model 222 with code 810 (Sound system) or with code 811 (Advanced sound system))
During in-car communication, the signals captured by the driver hands-free system microphone and the front passenger hands-free system microphone are evaluated, amplified and output via the speakers in the rear. Consequently, the driver or front passenger comments can be heard better in the rear.
It is not possible to output any comments from the rear through the front speakers.
The head unit sends the signals of the driver hands-free system microphone and the front passenger hands-free system microphone over MOST to the sound system amplifier control unit (with code 810 (Sound system)) or to the Advanced sound system amplifier control unit (with code 811 (Advanced sound system)).
Additional function requirements for active engine noise compensation (AMGK) (with code 97B (Engine noise reduction via speakers))
- Internal combustion engine running.
Active engine noise compensation (AMGK) (with code 97B (Engine noise reduction via speakers))
With active engine noise compensation, disturbing, low-frequency engine noises that are audible in the vehicle interior during engine operation on cylinder shutoff are reduced through the generation of counter-noise via the speaker system (LSA).
To calculate the precise actuation of specific LSA speakers, the sound system amplifier control unit (with code 810 (Sound system)) or the Advanced sound system amplifier control unit (with code 811 (Advanced sound system)) requires the engine speed from the ME-SFI [ME] control unit via the drive train CAN and the microphone signals of the following microphones via a direct line:
- Left front active engine noise compensation microphone
- Right front active engine noise compensation microphone
- Left rear active engine noise compensation microphone
- Right rear active engine noise compensation microphone
Disturbing, low-frequency noises in the overall vehicle interior noise are detected on the basis of the engine speed and the microphone signals.
In vehicles with code 810 (Sound system), the following speakers are actuated by the sound system amplifier control unit:
- Left footwell woofer
- Right footwell woofer
- Active engine noise compensation subwoofer
In vehicles with code 811 (Advanced sound system), the following speakers are actuated by the Advanced sound system amplifier control unit:
- Left footwell woofer
- Right footwell woofer
- Left front door woofer/midrange speaker (model 217.3)
- Right front door woofer/midrange speaker
- Left rear door midrange speaker/tweeter (model 222)
- Subwoofer via subwoofer amplifier
Acoustic operation feedback
The speaker system is actuated by the head unit for acoustic operation feedback when handling the touchpad (A105). For this function, the head unit evaluates control signal incoming from the touchpad, and calculates outgoing control signals for the speaker system. In vehicles with code 810 (Sound system), the head unit sends the signals over MOST to the sound system amplifier control unit, and with code 811 (Advanced sound system) to the Advanced sound system amplifier control unit.
| Electrical function schematic for speaker system | Model 217 as of model year 2018 | PE82.62-P-2300-97SEN | |
| Model 222 as of model year 2018 | PE82.62-P-2300-97SEM | ||
| Overview of system components, telematics | GF82.85-P-9999LFM |