GF54.00-P-0005AM CAN Data Bus, Function
GF54.00-P-0005AM CAN Data Bus, Function
MODEL 215 with ENGINE 113.991
MODEL 220 with ENGINE 113.991
MODEL 230 with ENGINE 113.992 /995 up to Model Year 8
A1 Instrument cluster
A89n1 DTR control unit (for Distronic from 07/04)
N2/7 Restraint systems control unit
N3/10 ME control unit
N10/6 Left front SAM control unit (models 215, 220)
N10/7 Right front SAM control unit (model 215, 220)
N10/8 Rear SAM control
N10/10 Driver-side SAM control unit (model 230)
N10/11 Front passenger SAM control unit (model 230)
N15/3 EGS control unit
N15/5 Electronic selector lever module control unit
N22 AAC [KLA] control and operating unit
N47-5 ESP, SPS [PML] and BAS control unit
N63/1 DTR control unit (for Distronic up to 06/04)
N73 EIS [EZS] control unit
N80 Steering column module
N93 Central gateway control unit
X11/4 Data link connector
CAN B CAN data bus, body
CAN-C CAN data bus, engine
CAN-D CAN data bus diagnosis
CAN stands for " Controller Area Network". This is an electrical bus system for carrying data over two wires.
The tasks are:
^ Data transfer between individual control units
^ Readying sensor signals for several systems
^ Reducing the number of electric cables
^ Improving the electromagnetic compatibility (EMC)
The CAN data bus consists of a special twisted two-core data line that connects all CAN users (control units) in parallel.
The two lines of the data line must not be mixed up (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) engine CAN data bus (CAN-C) for the power plant and chassis systems and the slower (83.3 kbit/s) body CAN data bus (CAN-B) structure for the vehicle interior.
In addition for the vehicle diagnosis with STAR DIAGNOSIS there is a diagnosis CAN data bus (CAN-D) with a speed of 500 kbit/s.
The interface between the three CAN data buses (Gateway) is located in the central gateway control unit.
The instrument cluster, electronic ignition switch control unit and the steering column module are connected with both the body CAN data bus and the engine CAN data bus and exchange data with both data bus systems.
However they do not serve as an interface (Gateway) between tow data bus system
When a control unit is replaced, the new control unit must be coded again.
This control unit coding is possible 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.
