GF54.00-P-0005AX CAN Data Bus, Function

GF54.00-P-0005AX CAN Data Bus, Function
MODEL 216 with ENGINE 156.984 up to Model Year 8
MODEL 221 with ENGINE 156.984 up to Model Year 8





A1 Instrument cluster
A80 Intelligent servo module for DIRECT SELECT
A89 DTR controller unit (with code 219 Distronic (DTR))
N2/7 Restraint systems control unit
N3/10 ME control unit
N10/1 Front SAM control unit with fuse and relay module
N10/2 Rear SAM control unit with fuse and relay module
N22/1 AAC [KLA] control unit
N47-5 ESP control unit
N62/1 Radar sensors control unit (SGR) (with code 233 Distronic Plus)
N73 EIS [EZS] control unit
N80 Steering column module
N93 Central gateway control unit
N118/3 Left fuel pump control unit
X11/4 Data link connector
Y3/8 Electric controller unit (VGS)
B Interior CAN
C Drive train CAN
D Diagnostic CAN
E Chassis CAN
F Central CAN
H Vehicle dynamics CAN

Can stands for "Controller Area Network". This is an electrical bus system for carrying data over two wires.
The tasks are:
^ Data exchange between individual control units
^ Readying sensor signals for several systems
^ Reducing the number of electrical lines
^ Improving the electromagnetic compatibility (EMC)
The CAN data bus consists of a special twisted two-core data line that connects all CAN subscribers (control units) in parallel.
The two lines of the data line must not be swapped (low level/high level). The ME control unit always represents a terminal with regard to bus adaptation.
A 120 ohms terminating resistor is therefore installed in the motor electronics control unit.
The data are transmitted digitally over the CAN databus 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. Each connected control unit is able to transmit or receive data (bidirectional bus).
The sum of the data blocks, the short break between the two transfer intervals and other properties of the CAN data bus are checked constantly. Detected faults are stored and placed in the fault memory.
In the vehicle a distinction is made between the fast (500 kbit/s) drive/chassis/vehicle dynamics and diagnostic CAN data buses and the slower (83,3 kbit/s) central and interior CAN data buses.
The interface (gateway) between the chassis/central/diagnosis and interior CAN-data bus is located in the central gateway control unit.
The interface between the chassis data bus and drive train CAN data bus is located in the ME-SFI [ME] control unit. The interface between the chassis data bus and vehicle dynamics CAN data bus is located in the ESP control unit.
The EIS [EZS] control unit and radar sensors control unit (with code 233 Distronic Plus) are connected with two CAN data buses and exchange data with two data buses.
However, they do not serve as an interface between the CAN data buses
When a control unit is replaced, the new control unit must be coded again.
This control unit coding takes place via a STAR DIAGNOSIS menu.
The international standardized network management "OSEK" (Open systems and their Interfaces for Electronics in motor vehicles) is used for all control units of the CAN data bus.