CAN-Bus, Function

Bus:
The term bus refers to a system that transports and distributes data.

CAN:
The Controller Area Network is a bus system that uses two wires. These are called bus wires. Data is transferred to the connected control modules serially (one after the other) across the bus wires.

Data is transferred via the CAN-bus. For information and test procedure. The CAN-bus only contains two lines. These are called bus wires. These transfer all required data. Two bus wires are used so that malfunctions in the wires can be recognized.

The CAN-bus terminates in a resistor. It prevents the transmitted data from returning as an echo from the ends and corrupting data.

The terminal resistances of the CAN-bus have a value of 120 52 and are located in the ABS control module (w/EDL) -J104- and the Engine Control Module (ECM) -item 3-. This results in an overall terminal resistance of approximately 60 A.

The steering angle sensor-G85- transmits its data to the control module via the CAN-bus. It does not have a terminal resistance.

As of implementation of control module 8D0 907 389 D/E, the CAN-bus is connected centrally in the Engine Control Module (ECM) with a resistance of approximately 66 ohms. All other control modules connected to the CAN system (for example the ABS control module -J104-) are connected with a high ohm resistance of 2.6 ken.