Audio tuner control unit, component description - GF82.62-P-3132LES

MODEL 216, 221 with CODE (810) Sound system as of model year 2009/YoM 08 

MODEL 221 with CODE (811) Advanced sound system except CODE (494) USA version as of model year 2011/YoM 10 

Shown on model 221 with CODE (810) Sound system 

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), processes and amplifies their audio signals.

On model 221 as of 1.9.10 (with code (811) Advanced Sound System) the audio tuner control unit only functions as a radio tuner and it does not actuate any speakers. Audio output here is through the digital sound processor (A2/69) and the sound amplifier (A2/13).

The audio tuner control unit also performs the following tasks:

• Reading in of signals 
• Processing signals 
• Transmit 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 (except model 221 as of 1.9.10 with code (811) Advanced Sound System)
• Wake-Up
• Antenna signals from the rear window antenna amplifier module (A2/12)
• Signals from 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) (except model 221 as of 1.9.10 with code (811) Advanced Sound System)
  • Emergency call system control unit (N123/4) (with code (359) TELE AID emergency call system) (except model 221 as of 1.9.10 with code (811) Advanced Sound System)

Processing signals 

The audio tuner control unit processes the following signals:

• Copy protected audio signals (except model 221 as of 1.9.10 with code (811) Advanced Sound System)
• DVD audio signals
• Radio signals
• Vehicle speed signal for the speed-dependent volume control (SDV) (except model 221 as of 1.9.10 with code (811) Advanced Sound System)
• Voice input from the sound amplifier microphone for dynamic range optimization (DRO) (up to 31.5.09)

Transmit signals 

The signals are transmitted via the following connections:

• MOST 

MOST 

The following signals are transmitted via MOST:

• Audio signals to the digital sound processor (model 221 as of 1.9.10 with code (811) Advanced Sound System)
• Traffic messages to COMAND controller unit

Actuation of components (except model 221 as of 1.9.10 with code (811) Advanced Sound System) 

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 (except model 221 as of 1.9.10 with code (811) Advanced Sound System)
• MOST interface
• Basic amplifier (audio signal output) (except model 221 as of 1.9.10 with code (811) Advanced Sound System)

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 F) 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 when traffic messages arrive ("TP Volume")
• Switch-off time for circuit 15 OFF

	Wiring diagram for radio (RD) control unit	Model 216	PE82.60-P-2101-97CAA
		Model 221	PE82.60-P-2101-97SAA