TV-Mode, Function - GF82.85-P-2011RD

Model 172.4 

up to model year 2017 

with code 865 (digital TV) 

Function requirement TV mode, general 

• Circuit 30g
• Transport mode not active
• "TV" menu item selected under "Video" menu item

TV mode, general 

The digital TV tuner (A90/3) enables digital television channels to be received in the vehicle and shown on the Audio/COMAND display (A40/8).

The COMAND controller unit (A40/3) switches off the TV picture when the vehicle starts moving. When the vehicle is moving, only acoustic playback remains active and - for safety reasons - a warning is shown on the Audio/COMAND display. The vehicle speed signal is received by the COMAND controller unit over the interior CAN (CAN B) from the instrument cluster (A1).

The TV functions can be selected, activated and adjusted using the following components: Audio/COMAND control panel (A40/9), left multifunction steering wheel button group (S110) and right multifunction steering wheel button group (S111).

The Audio/COMAND control panel sends the control signals as follows:

Telematics CAN (CAN A) →

COMAND controller unit →

Media Oriented System Transport (MOST) →

TV digital tuner

The control signals from the left multifunction steering wheel button group and the right multifunction steering wheel button group are sent by the steering wheel electronics (N135) as follows:

Steering LIN (LIN E1) →

Steering column tube module control unit (N80) →

Chassis CAN (CAN E) →

Instrument cluster →

Interior CAN →

COMAND controller unit →

MOST →

TV digital tuner

The digital TV tuner separates the video and audio signals from each other. The TV mode is therefore comprised as follows:

• Function sequence for TV signal reception 
• Function sequence for video signal 
• Function sequence for audio signal 
• Supplemental information 

Function sequence for TV signal reception 

The antenna signals for TV reception are received by the windshield antenna (A2/118) and forwarded as follows:

TV 1 antenna amplifier (A94/1) →

TV 2 antenna amplifier (A94/2) →

FM 2, DAB and TV antenna amplifier (A2/19) (for TV 3 signal) →

TV digital tuner

Function sequence for video signal 

After the TV signals have been processed in the digital TV tuner, the video signals are output as follows:

Y/C line (Y-brightness (luminance)/C-color information (chrominance)) →

COMAND controller unit →

LVDS (Low Voltage Differential Signal) line →

Audio/COMAND display

The control signals, e.g. switch-on request, are received by the Audio/COMAND display over the telematics CAN from the COMAND controller unit.

Function sequence for audio signal 

After the TV signals have been processed in the digital TV tuner, the audio signals are forwarded over the Media Oriented System Transport (MOST) to the COMAND controller unit, and on vehicles with code 810 (Sound system) forwarded over MOST to the sound system amplifier control unit (N40/3) where they are then amplified and emitted via the speaker system.

Supplemental information 

The digital TV tuner provides the following features:

• Digital image storage
• Last settings
• "BML" (Broadcast Markup Language) function:

  The digital TV tuner supports video text for all available Japanese TV stations. This means that, similar to a small website, weather information, news etc. can be shown. By selecting a prefecture in the setting list you can obtain regional information.

• "EPG" (Electronic Program Guide) function:

  The Electronic Program Guide displays information such as start of program, end of program and detailed information on the television programs for each TV station.

• "Bilingual" function:

  Two languages are supported depending on station availability, e.g. Japanese on the main soundtrack and English on the sub-soundtrack.

	Electrical function diagram for TV mode, function		PE82.85-P-2065-97TAA
	Overview of system components, telematics		GF82.85-P-9999RD