Bus Structures; All Models From E38 And Mini: Introduction
In the vehicles of today, components and control units are networked by means of data buses. Data buses are capable of transmitting messages and signals.
The connected control units only read off those messages and signals that are of relevance to their operation.
Most buses are CAN buses (CAN: Controller Area Network).
A fibre-optic cable is used for navigation and entertainment: The MOST bus (MOST = "Media Oriented System Transport").
It has its own data wire for diagnosis: the diagnostics cable, also known as the "K-line"
In the overviews of bus structures, all diagnosis and programming control units are indicated by abbreviations.
The following control units are numbered:
- Control units that cannot be programmed and cannot be encoded and which do not appear in the quick test.
These control units do not have an abbreviation, just a number.
- Control units with control unit designation from the time before electrical system 2000:
Besides the abbreviation, these control units have a number for entering in the table.
On the history of control unit designations:
Since the start of series production of the E65 (electrical system 2000), the control unit designations have been harmonized. Earlier model series have varying control unit designations.
For technical reasons associated with the system, these control units have not been renamed.
This is because: These control unit designations appear in the quick test on the BMW diagnosis system.