Modular tachograph (MTCO), component description

D54.61-1157-05

A56 Tachograph

N72/1 OBF control unit

Location

The tachograph is located in the instrument panel below the OBF control unit.

Task

The tachograph has the following tasks:

 Operation options over control buttons, e.g. calling up of menu content for diagnostic data or selection of respective working time groups for drivers 1 and 2

 Comparison of real-time signal (analog signal) with encoded, digital signals as well as verification of serial number of speed sensor (B6/12)

 Transmission of data and command signals to speed sensor

 Calculation of ground speed and travel distance

 Display of following information on tachograph display:

- Date

- Time

- Odometer reading

- Set time groups

- Symbols of inserted tachograph disks and individual menu items, e.g. fault memory or programming data

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 Registration of following 4 time groups

- Steering time

- Standby time

- Break times and rest times

- Other working hours

 Detection of following information:

- Real-time signal (analog signal) and encoded, digital signals for rotational speed of transmission output shaft

- Serial number of speed sensor

 Documentation of following information on tachograph disk(s) with precise time specification:

- Vehicle speed

- Travel distance

- 4 time groups

- Special events, e.g. voltage interruptions or faults at speed sensor

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 Monitoring of system for following faults by means of integrated diagnostic function, storage of diagnosed fault in event or fault list and automatic display of diagnosed fault in tachograph display:

- Voltage interruption

- Faulty signals from speed sensor

- System faults

- Operating errors

 Transmission of diagnostic information to EIS [EZS] control unit (N73) via Controller Area Network bus class C (engine compartment) (CAN-C)

 Communication with instrument cluster (A1) via CAN-C

 Actuation of switch and controls illumination for buttons integrated in tachograph

 An entry on the tachograph disk or tachograph disks ensues depending on the diagnosed fault.

N54.61-2114-09

Design

30 Left button panel

31 Display

32 Right button panel

33 Drawer

34 Separator plate

35 Inspection marking

32a Minus button

32b Button for time group settings, driver 2

32c Plus button

32d Menu button

A56 Tachograph

36 Oval tachograph disc support

37 Model plate

30a Unlock drawer button

30b Button for time group settings, driver 1

 It is not possible to fold down the drawer. The illustration is simply intended to provide a better understanding of the design.

N54.61-2115-01

Display setup

31 Display

31a Date display

31b time display

31c Time display group symbol, driver 1

31d Display of tachograph disk symbol, driver 1

31e Display of total kilometer reading

31f Fault symbol display

31g Display of tachograph disk symbol, driver 2

31h time display group symbol, driver 2