TV-mode, function - GF82.85-P-2011A

MODEL 215, 220 with CODE (352) COMAND operating and display system with CODE (860) TV tuner

Fig 1: TV-Mode Function Diagram - Without Code (810) Sound System Up To 31.8.03

COMAND TV system block diagram, without Code (810) Sound system up to 31.8.03

Fig 2: TV-Mode Function Diagram - Without Code (810) Sound System As Of 1.9.03

Block diagram of COMAND TV system, without sound system code (810) as of 1.9.03

On vehicles as of 1.9.03, the TV tuner (MOST) (A2/10) is integrated in the Media Oriented System Transport (MOST). Thus, the data exchange (audio and video signals) with the other TV components takes place via this fiber optical cable.

On vehicles as of 1.9.03, the audio gateway control unit (N93/1) is also installed as an interface between the Controller Area Network bus class B (interior) (CAN-B) and the MOST. The audio signals are then sent to the audio gateway control unit (N93/1) and output via the vehicle speakers.

TV system control

The TV tuner (A2/42) is controlled via the COMAND operating, display and control unit (A40/3). The communication between the COMAND operating, display and control unit (A40/3) and the TV tuner (A2/42) takes place via the Robert Bosch CAN (RB-CAN).

The COMAND TV system has the following features:

4-way TV antenna diversity
Multistandard capability, i.e. Color decoder for NTSC, PAL and SECAM standard with automatic detection
Videotext decoder
10 memory locations for the station list sorted by reception field strength and 10 further memory locations for freely selectable stations
SCAN function (the stations are played in succession)
On Screen Display (OSD) function (text displays on the screen)

The COMAND TV system provides a facility for connecting other video sources such as a video recorder or Camcorder. The relevant connectors are provided on the TV tuner (A2/42).

TV reception

The 4 TV antennas in the rear window receive the TV high-frequency signals completely independent from one another. The video and sound signals are modulated upon these high-frequency signals. The rear window antenna amplifier module (A2/12) filters the frequencies of the TV frequency bands from the high frequency signals and amplifies them. The amplified signals are led to the TV tuner (A2/42) via 4 separate coaxial cables.

The TV tuner (A2/42) selects the strongest of the incoming antenna signals (antenna diversity), selects the required transmitter and then demodulates the TV sound and TV video signals in accordance with the relevant transmission standard (e.g. NTSC). The video and sound signals prepared in this way are transferred as red-green-blue synchronous video signals (RGBS) as well as low-frequency signals (LF) for the audio signals (TV sound) to the COMAND operating, display and control unit (A40/3) and the operating and display unit rear monitor (A40/2).

TV picture display

up to 31.8.02

The TV picture is only shown on the display of the COMAND operating, display and control unit (A40/3) under the following prerequisites:

The parking brake has to be actuated and the selector lever has to be in the "P" or "N" position (both pieces of information come via the CAN-B).

as of 1.9.02

The display in the COMAND operating, display and control unit (A40/3) switches off automatically at a speed of v > 8 km/h. In contrast to this, the pictures are also displayed on the rear monitor operating and display unit (A40/2) while driving. The TV system can then also be operated from the rear by remote control.

TV sound playback (up to 31.8.03)

The TV tuner (A2/42) forwards the TV audio signal to the COMAND operating, display and control unit (A40/3) via separate lines.

The signals are then amplified and converted into acoustic signals by the vehicle speakers. 2 sets of headphones can be connected to the operating and display unit rear monitor(A40/2). Only the TV sound can be heard on these headphones, regardless of the audio source that is being played on the vehicle speakers.

With code (810) Sound system, the TV audio signals are sent from the COMAND operating, display and control unit (A40/3) via the Digital Data Bus (D2B) to the sound amplifier (A2/13), where they are received, amplified and then converted into acoustic signals via the vehicle speakers.

TV mute function (as of 1.6.01)

The mute status of the audio sources (muting) is maintained if it was activated before switching off.

Displaying mute status in the TV screen

If audio sources are muted, a symbol appears in the top right of the display.

To be able to display on the TV screen that the mute function is active, the corresponding message has to be transmitted to the TV tuner (A2/42).

The setting which was performed last before switching off the ignition, is adopted when the ignition is switched on again.

Antenna amplifier module, location/task/design/function		GF82.62-P-3105A
Rear monitor, location/task/design/function	Model 220 up to 31.8.02 With code (861) Rear TV screen except CODE (498) Japanese version except CODE (494) USA version	GF82.60-P-3101A
	Model 220 as of 1.9.02 With code (861) Rear TV screen except CODE (498) Japanese version except CODE (494) USA version	GF82.60-P-3101AS
TV tuner, location/task/design/function	up to 31.8.03 except CODE (498) Japanese version except CODE (494) USA version	GF82.60-P-3109C
	as of 1.9.03 except CODE (498) Japanese version except CODE (494) USA version	GF82.60-P-3109CA
Rear window antenna, location/task/design/function		GF82.62-P-3106A
Audio gateway control unit, location/task/design	as of 1.9.03	GF82.62-P-3116SZ