BMW 7 Series: System Overview

Audio playback takes place either through the vehicle's speakers or via headphones. The volume of the speakers can be adjusted via the multifunction steering wheel, the head unit or with the remote control. The volume is controlled speed-dependent during playback through the speakers. The driving speed is registered by the wheel speed sensors.

The sound settings can be configured on the CIC or with the remote control. If audio is played back via the headphones, the volume can be adjusted either on the headphones (infrared headphones) or using the remote control (hard-wired headphones). The infrared headphones receive their signals from the infrared transmitter.

Fig. 1: Identifying Rear Seat Entertainment System (RSE)

External devices can be connected via the two AV inputs directly to the RSE control unit or via the AUX-In connection or the USB-audio interface in the center console. The USB-audio interface provides an additional jack and a USB connection for a type A USB connector.

Fig. 2: Rear Seat Entertainment System Function Diagram

REAR SEAT ENTERTAINMENT SYSTEM COMPONENTS REFERENCE CHART

1. Central information display (CID)
2. Head unit, Car Information Computer (CIC)
3. iDrive controller
4. Central gateway module (ZGM)
5. Rear display FD2 with rear display control unit and infrared transmitter
6. Infrared headphones
7. Rear display FD with rear display control unit and infrared transmitter
8. Remote control
9. Rear seat entertainment control unit (RSE MID)
10. DVD changer (DVD)
11. Video switch (VSW)
12. Not for US

When playing a DVD in the CIC, the picture cannot be transmitted to the rear seat entertainment system. When playing a DVD in the RSE control unit the picture is not transmitted to the CIC. However audio playback is possible in both cases.

During playback via the DVD changer, picture and sound are transmitted to the CIC and the rear seat entertainment system.

For safety reasons, no picture is shown in the CID while the vehicle is being driven, although audio playback is still possible.

When an external device (e.g. game console) is connected to one of the AV inputs of the RSE control unit, the video signal is output on the right or left display depending on where the source is connected. A selected DVD can still be viewed on the other display.

The RSE control unit features a FBAS or CVBS (composite video baseland signal) video signal input.

The RSE control unit has a CVBS video signal input connected to the DVD Changer through the video switch to display of media played in the DVD Changer on the rear screens. In this case the video switch is needed because a source with a CVBS output (e.g. DVD changer) is connected to the CIC and the RSE.

The CIC has only three CVBS inputs, If there are more than three video sources to be connected to the CIC a video switch has to be included to comply with the equipment configuration.

NOTE: (FBAS) Farb-Bild-Austast-Synchron is CVBS (Composite Video Baseband Signal) in which just the video signal is transmitted through a single wire with the audio signal handled separately.

RSE Circuit Diagram

Fig. 3: RSE Circuit Diagram

INDEX REFERENCE CHART

1. Central gateway module (ZGM)
2. Car Information Computer (CIC)

4. Infrared transmitter, right
5. Rear display (FD2) with rear display control unit (SG-FD2)
6. Fuse
7. Video switch (VSW)
8. Aerial diversity module with aerial amplifier
9. Rear seat entertainment control unit (RSE)
10. Rear display (FD) with rear display control unit (SG-FD)
11. Infrared transmitter, left
12. Car Access System 4 (CAS4)

KL.30B - Terminal 30 basic operation
KL.58G - Signal, footwell module light (FRM 3)
FBAS - FBAS signal
IR - Infrared signal
K-CAN - Body CAN
K-CAN2 - Body CAN2
LVDS - Low voltage differential signal
MOST - Media Oriented System Transport

MOST Signals at RSE Control Unit

MOST SIGNAL REFERENCE CHART

K-CAN Signals at SG-FD and SG-FD2

K-CAN SIGNAL REFERENCE CHART

The FD and FD2 rear displays each have their own control unit. The SG-FD and SG-FD2 control units are connected to the K-CAN. The rear displays are connected via LVDS to the RSE control unit. All video information is transmitted via the LVDS link. The rear displays receive the ON/OFF signal from the RSE control unit. The ZGM places the MOST signal on the K-CAN and is sent to the rear displays.

During audio playback through the vehicle's speaker system, the RSE control unit routes the audio signal via the MOST to the head unit CIC or the Top-HiFi amplifier.

Programming, coding and diagnosis of the rear seat entertainment system (6FG) take place via MOST.

Fig. 4: Rear Seat Entertainment System Remote Control Function Diagram

INDEX REFERENCE CHART

1. Remote control
2. Rear window with antenna, remote control services (FBD)
3. Antenna diversity module with antenna amplifier
4. Car access module 4 (CAS4)
5. Central gateway module (ZGM)
6. Rear seat entertainment control unit (RSE)

The commands entered by means of the remote control are transmitted by radio waves.

The same frequency is also used for the radio remote control key. The frequency used is dependent on the national variant and therefore relevant for coding. The commands are received by the FBD antenna and routed via the antenna diversity module to the CAS4.

The CAS4 converts the signals into K-CAN2 messages and routes the signals to the ZGM. The ZGM places the signals on the MOST-bus. The RSE control unit receives the signals via the MOST.

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