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GF00.19-P-0001FL Overall Network (GVN) Function




GF00.19-P-0001FL Overall Network (GVN) Function
- MODEL 212.0/ 2

General overall network
The increased demands that are made of the vehicle electronics in areas such as the following:
- Vehicle safety
- Comfort
- Communication
- Diagnosis
require networking of the existing systems in the vehicle so that the necessary information can be exchanged.

This cannot be achieved using conventional data transfer since the amount of installation space is limited and a reduction of the weight of the vehicle is targeted. This is why data bus systems are used.

The vehicle electronics are networked using the following data bus systems:
- Controller Area Network (CAN)
- Media Oriented System Transport (MOST)

CAN
The CAN is an electrical bus system for the transmission of data via two lines.
The CAN consists of a twisted two-core data line that connects all CAN participants (control units) via a parallel connection.
The two lines of the data line must not be swapped (low level/high level). Each connected control unit is able to transmit or receive data (bidirectional bus). The data are sent digitally over the CAN at various intervals. The individual data blocks are defined in a data protocol and it is specified which data are received or transmitted by a control unit.
The sum of the data blocks, the short break between two transmission intervals and other properties of the CAN are checked constantly. Detected faults are stored and placed in the fault memory.

The CAN offers the following advantages:
- Data exchange between individual control units
- Provision of sensor signals for several systems
- Reduction of the number of electrical lines
- Improved electromagnetic compatibility (EMC)

The following CAN systems are involved in the overall network:
- Telematics CAN (CAN A)
- Interior CAN (CAN B)
- Drive train CAN (CAN C)
- Diagnostic CAN (CAN D)
- Chassis CAN (CAN E)
- Front end CAN (CAN G)
- Vehicle dynamics CAN (CAN H)
- Drive train sensor CAN (CAN I)
- Sensor CAN (CAN S)

Telematics CAN
The telematics CAN is used for the data exchange of the attached audio components with one another.
The telematics CAN operates at a transfer rate of 125 kBit/s.

The following control units are subscribers to the telematics CAN:
- Radio (A2) (with code (523) MB Audio 20 radio or code (510) Audio 20 with CD changer)
- Radio with auto pilot system (A2/56) (with code (525) MB Audio 50 APS radio or code (511) Audio 50 APS with DVD changer)
- COMAND controller unit (A40/3) (with code (527) COMAND APS with single DVD drive (with navigation) or code (512) COMAND APS with DVD changer or code (528) COMAND with DVD changer)
- DVD player (A40/4) (with code (864) Rear entertainment system)
- Left rear display (A40/5) (with code (864) Rear entertainment system)
- Right rear display (A40/6) (with code (864) Rear entertainment system)
- Audio/COMAND display (A40/8)
- Audio/COMAND control panel (A40/9)

Gateway:
The radio or COMAND controller unit forms the interface for the data exchange between the telematics CAN and other bus systems.

Interior CAN
The interior CAN is used for the data exchange of the attached control units with one another. The interior CAN operates at a transfer rate of 125 kBit/s.

The following control units are subscribers to the interior CAN:
Instrument cluster (A1)
Stationary heater control unit (A6n1) (with code (228) Stationary heater)
Radio or COMAND controller unit
Panoramic sliding roof control module (A98) (with code (413) Panoramic glass sunroof with top sliding sunroof)
Pneumatic pump for dynamic multicontour seat (M40/1) (with code (432) Left and right dynamic multicontour seat)
Front SAM control unit with fuse and relay module (N10/1)
Rear SAM control unit with fuse and relay module (N10/2)
Automatic air conditioning control and operating unit (N22/7)
Rear seat heater control unit (N25/6) (with code (872) Electrically heated left and right rear seats)
Steering wheel heater control unit (N25/7) (with code (443) Steering wheel heater)
- Special-purpose vehicle multifunction control unit (N26/9) (with code (965) Electrical preinstallation for rental vehicles)
- Trailer recognition control unit (N28/1) (with code (550) Trailer hitch)
- Driver seat control unit (N32/1) (with code (275) Memory package for electrically adjustable front seats)
- Front passenger seat control unit (N32/2) (with code (275) Memory package for electrically adjustable front seats)
- Left front dynamic multicontour seat control unit (N32/19) (with code (432) Left and right dynamic multicontour seat)
- Right front dynamic multicontour seat control unit (N32/22) (with code (432) Left and right dynamic multicontour seat)
- Reversing camera control unit (N66/2) (with code (218) Reversing camera and code (498) Japan version)
- Left front door control unit (N69/1)
- Right front door control unit (N69/2)
- Left rear door control unit (N69/3)
- Right rear door control unit (N69/4)
- Keyless-Go control unit (N69/5) (with code (889) Keyless-Go)
- Overhead control panel control unit (N70) (with code (414) Power glass tilting/sliding sunroof)
- Electronic ignition lock control unit (N73)
- WSS (Weight Sensing System) control unit (N110) (with code (494) USA version)
- KDS [trunk lid-control control unit] (N121) (on model 212.0 with code (881) Remove trunk closing (HDFS))
- Liftgate control unit (N121/1) (on model 212.2)

Gateway:
The following control units form the interface for the data exchange between the interior CAN and other bus systems:
- Front SAM control unit
- Radio or COMAND controller unit

The electronic ignition lock control unit and the instrument cluster are also connected to the chassis CAN but do not have a gateway function.

Drive train CAN
The drive train CAN is used for exchanging data between the connected control units. The drive train CAN operates at a transfer rate of 500 kBit/s.

The following control units use the drive train CAN:
- Intelligent servo module for DIRECT SELECT (A80) (with transmission 722.9)
- CDI control unit (N3/9) (on diesel engine)
- ME-SFI [ME] control unit (N3/10) (on gasoline engine)
- Electronic transmission-control control unit (N15/3) (on transmission 722.6)
- Electronic selector lever module control unit (N15/5) (with transmission 722.6)
- Transmission oil auxiliary pump control unit (N89) (with code (B03) ECO start/stop function)
- Fuel pump control unit (N118) (on gasoline engine)
- CNG control unit (N118/2) (with engine 271.958)
- Transmission mode control unit (N145) (in model 212.074/077/274/277)
- DIRECT SELECT INTERFACE (N150) (in model 212.074/077/274/277)
- Fully integrated transmission control unit (Y3/8n4) (with transmission 722.9)

Gateway:
The CDI control unit or ME-SFI control unit forms the interface for data exchange between the drive CAN and other bus systems.

Diagnostic CAN
The diagnostic CAN is used for the data exchange of the external diagnostic tester with the control units in the vehicle. The diagnostic CAN operates at a transfer rate of 500 kBit/s.

The following control units are subscribers to the diagnostic CAN:
- Front SAM control unit
- Emergency call system control unit (N123/4) (for code (359) TELE AID emergency call system)

Gateway:
The front SAM control unit forms the interface for the data exchange between the diagnostic CAN and other bus systems.

Chassis CAN
The chassis CAN is used for the data exchange between the attached control units. The chassis CAN operates at a transfer rate of 500 kBit/s.

The following control units are chassis CAN subscribers:
- Instrument cluster
- Multifunction camera (A40/11) (with code (238) Active Lane Keeping Assist, code (476) Automatic Lane Recognition, code (513) Speed Limit Assist or code (608) Adaptive Highbeam Assist)
- Left front reversible emergency tensioning retractor (A76)
- Right front reversible emergency tensioning retractor (A76/1)
- Supplemental restraint system control unit (N2/10)
- CDI control unit or ME-SFI [ME] control unit
- Front SAM control unit
- Electronic Stability Program control unit (N30/4) (without code (233) DISTRONIC PLUS, except model 212.074/077/274/277)
- Premium Electronic Stability Program control unit (N30/7) (with code (233) DISTRONIC PLUS or model 212.074/077/274/277)
- AIRmatic control unit (N51/3) (with code (488) Steel/air suspension or with code (489) AIRmatic (air suspension with continuously adjustable damping))
- Parking system control unit (N62) (with code (220) PARKTRONIC or code (230) Exclusive parking assist)
- Radar sensors control unit (N62/1) (up to 31.5.10 with code (233) DISTRONIC PLUS or code (234) Blind Spot Assist)
- Video and radar sensor system control unit (N62/2) (as of 1.6.10 with code (233) DISTRONIC PLUS, code (237) Active Blind Spot Assist or code (238) Active Lane Keeping Assist)
- Electronic ignition switch control unit
- Steering column module control unit (N80)
- Tire pressure monitor control unit (N88) (with code (475) Tire pressure monitor (premium))
- Rear axle electronic level control control unit (N97) (in model 212.2 without code (489) AIRmatic (air suspension with continuously adjustable damping) and without code (488) Steel/ air suspension)
- Night view assist control unit (N101) (with code (610) Night view assist)
- Transmission mode control unit (for model 212.074/077/274/277)

Gateway:
The following control units form the interface for the data exchange between the chassis CAN and the other bus systems:
- Front SAM control unit
- CDI control unit or ME-SFI [ME] control unit

Front end CAN
The front end CAN is used for the data exchange of the attached control units with one another. The front end CAN operates at a transfer rate of 500 kBit/s.

The following control units are front end CAN subscribers:
- Front SAM control unit
- As of 1.6.10 with code (234) Blind Spot Assist:
- Left rear bumper intelligent radar sensor (B29/4)
- Right rear bumper intelligent radar sensor (B29/5)
- With code (615) Bi-xenon headlamp unit with integrated curve illumination or code (616) Bi-xenon headlamp unit with integrated asymmetrical curve illumination or code (621) Intelligent Light System (left-hand traffic) or code (622) Intelligent Light System (right-hand traffic):
- Left xenon light control unit (E1n1)
- Right xenon light control unit (E2n1)

Gateway:
The front SAM control unit forms the interface for the data exchange between the front end CAN and other bus systems.

Vehicle dynamics CAN
The vehicle dynamics CAN is used for data exchange between the attached control units. The vehicle dynamics CAN operates at a transfer rate of 500 kBit/s.

The following control units are subscribers to the vehicle dynamics CAN:
- DISTRONIC electric controller unit (A89) (with code (233) DISTRONIC PLUS or as of 1.6.10 with code (237) Active Blind Spot Assist)
- Yaw rate, lateral and longitudinal acceleration sensor (B24/15)
- Electronic Stability Program control unit (without code (233) DISTRONIC PLUS, without model 212.074/077/274/277)
- Premium Electronic Stability Program control unit (with code (233) DISTRONIC PLUS or on model 212.074/077/274/277)
- Radar sensors control unit (up to 31.5.10 with code (233) DISTRONIC PLUS or code (234) Blind Spot Assist)
- Video and radar sensor system control unit (as of 1.6.10 with code (233) DISTRONIC PLUS, code (237) Active Blind Spot Assist or code (238) Active Lane Keeping Assist)

Gateway:
The Electronic Stability Program control unit forms the interface for data exchange between the vehicle dynamics CAN and the other bus systems.

Drive train sensor CAN
The drive train sensor CAN is used for the data exchange of the attached control units with one another. The drive train sensor CAN operates at a transfer rate of 500 kBit/s.

The following control units are subscribers to the drive train sensor CAN:
- CDI control unit or ME-SFI [ME] control unit
- Left nitrogen oxides control unit (N37/5) (with engine 272.98)
- Right nitrogen oxides control unit (N37/6) (with engine 272.98)
- Nitrogen oxides control unit downstream of diesel particulate filter (N37/7) (with engine 642.8 with code (U42) BlueTEC (SCR) diesel exhaust treatment)
- Nitrogen oxides control unit downstream of SCR catalytic converter (N37/8) (with engine 642.8 with code (U42) BlueTEC (SCR) diesel exhaust treatment)
- AdBlue� control unit (N118/5) (with engine 642 with code (U42) BlueTEC (SCR) diesel exhaust treatment)

Gateway:The CDI control unit or ME-SFI [ME] control unit forms the interface for data exchange between the drive sensor CAN and other bus systems.

Sensor CAN
The sensor CAN is used for data exchange between the attached control units. The sensor CAN operates with a transfer rate of 500 kBit/s.

The following control units are subscribers to the sensor CAN:
- Left front bumper DISTRONIC (DTR) sensor (B29/2) (with code (233) DISTRONIC PLUS)
- Right front bumper DISTRONIC (DTR) sensor (B29/3) (with code (233) DISTRONIC PLUS)
- Left rear bumper radar sensor (B29/6) (with code (234) Blind Spot Assist or code (237) Active Blind Spot Assist)
- Right rear bumper radar sensor (B29/7) (with code (234) Blind Spot Assist or code (237) Active Blind Spot Assist)
- Radar sensors control unit (up to 31.5.10 with code (233) DISTRONIC PLUS or code (234) Blind Spot Assist)
- Video and radar sensor system control unit (as of 1.6.10 with code (233) DISTRONIC PLUS, code (237) Active Blind Spot Assist or code (238) Active Lane Keeping Assist)

Gateway:
The radar sensors control unit or the video and radar sensor system control unit forms the interface for data exchange between the sensor CAN and other bus systems.

MOST
MOST is an optical data bus system.
Here, data are transferred via fiber optic cable to the connected information, navigation, and communication components. The MOST operates with a transfer rate of 22 Mbits/s.

The following control units are subscribers to the MOST:
- Radio or COMAND controller unit
- TV tuner (analog/digital) (A90/1) (with code (863) Digital/analog TV tuner)
- Digital TV tuner (A90/3) (with code (527) COMAND APS with single DVD drive (with navigation) and code (498) Japan version)
- Sound system amplifier control unit (N40/3) (with code (810) Sound system)
- Digital Audio Broadcasting control unit (N87/3) (with code (537) Digital radio)
- Satellite digital audio radio (SDAR) control unit (N87/5) (as of 1.6.10 with code (536) SIRIUS satellite radio)
- SDAR/high definition tuner control unit (N87/8) (up to 31.5.10 with code (536) SIRIUS satellite radio)
- Media interface control unit (N125/1) (with code (518) Media interface)

Gateway:
The radio or COMAND controller unit forms the interface for the data exchange between the MOST and other bus systems.