Diagnostics Master: Notes

The Diagnostics Master function is a function distributed throughout the vehicle. It is divided into the following subfunctions:

• Time Master 

Includes the centralized specification of a system time for all control units in the vehicle, and the application as a time stamp for fault messages from control units.

• Centralized fault memory 

Includes the saving of fault and Check Control messages with centralized ambient conditions.

• Specification of the fault memory status 

Includes the centralized specification a fault memory block for network fault memory entries in specific situations as well as the evaluation/application of the block in the client control units.

One task is often divided over multiple computers in a computer network (this also includes control units with bus connections). It is important to specify the computer (or control unit) that has the main function. This control unit is then described as the main control unit or "master". All other computers (control units) are called "peripherals" or "secondary controllers".

Each subfunction of the diagnostics master includes a master portion and a secondary portion. The master portion is always implemented in a single control unit, but the secondary controller portion in all participating control units.