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Ignition Switch: Description and Operation




GF80.57-P-6001RD Component Description For the Electronic Ignition Lock Control Unit
MODEL 172.4





N73 Electronic ignition switch control unit

Location
The electronic ignition lock control unit is located on the right, next to the steering column.

Task
The electronic ignition lock control unit has the following tasks:
^ Reading in of signals
^ Evaluation of input factors
^ Actuation of components
^ Power supply for transmitter key (A8/1)

Reading in of signals
The input factors are read in via the following connections:
^ Direct line
^ Interior CAN (CAN B)
^ Chassis CAN (CAN E)

Direct line
The electronic ignition lock control unit communicates with the electric steering lock control unit (N26/5) via a serial data line.

Interior CAN
The signals are read in by the electronic ignition lock control unit via the interior CAN.
The functions resulting therefrom are described in the corresponding function descriptions (see block diagram or function schematic).

Chassis CAN
The signals are read in by the electronic ignition lock control unit via the chassis CAN.
The functions resulting therefrom are described in the corresponding function descriptions (see block diagram or function schematic).

Evaluation of input factors
The input factors that have been read in are evaluated by the integrated microprocessor and the relevant components are then actuated.

Actuation of components
Components are actuated via the following lines:
^ Direct line
^ Interior CAN
^ Chassis CAN

Direct line
The following components are actuated via a direct line:
- C. 30 to electric steering lock control unit (locking voltage)
- Serial data line to electric steering lock control unit

Interior CAN
The signals are transmitted to the electronic ignition lock control unit via the interior CAN.
The functions resulting therefrom are described in the corresponding function descriptions (see block diagram or function schematic).

Chassis CAN
The signals are transmitted to the electronic ignition lock control unit via the chassis CAN.
The functions resulting therefrom are described in the corresponding function descriptions (see block diagram or function schematic).

Power supply for transmitter key
When the transmitter key is inserted into the electronic ignition lock control unit, it switches on the inductive power transmission for power supply to the transmitter key.