Volkswagen The Golf 2004 Service Training page 17

Master control unit
The control unit connected to the CAN data bus
takes on the master functions of the LIN data bus
system.
Tasks
Conversion of local data bus messages to data
format of CAN data bus
Monitoring of data bus conversion and rate of
data transfer
Control of data transfer cycle
Transfer of diagnosis data from slave control
units
The convenience system central control unit, illustrated, shows the wiring of the LIN and CAN data buses.
LIN data bus wires
Slave control unit
In the LIN data bus system, individual control
units, sensors or actuators can act as slave
control units.
The electronics integrated in the control units
evaluate the information, convert it into digital
information and send it, once the request has
been made, via the LIN data bus to the master
control unit.
Actuators are assigned their tasks by a signal,
which comes from the master control unit via the
LIN data bus.
Following interrogation of the master control
unit, the electronics integrated in the sensors
send the actual status to the master control unit,
in which a target/reference comparison is
carried out.
CAN data bus wires
S319_068
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