Instrument cluster, component description

P54.30-9881-76

Shown with code (494) USA version

A1 Instrument cluster

A1e1 Left turn signal indicator lamp

A1e2 Right turn signal indicator lamp

A1e3 High beam indicator lamp

A1e4 Fuel reserve indicator lamp

A1e7 Brake fluid and parking brake warning lamp

A1e9 Seat belt warning lamp

A1e15 Airbag indicator and warning lamp

A1e17 ABS indicator lamp

A1e30 ESP OFF indicator lamp

A1e41 ESP and ABS warning lamp

A1e54 Coolant temperature warning lamp

A1e58 Engine diagnosis indicator lamp

A1e66 Tire pressure monitor warning lamp
(with code (470) Tire pressure monitor (standard))

A1e69 Upshift recommendation lamp

A1p1 Coolant temperature gauge

A1p2 Fuel level and reserve indicator

A1p5 Tachograph

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A1p8 Electronic speedometer

A1p13 Left multifunction display

A1p15 Right multifunction display

A1r1 Instrument illumination brightness control and reset button

P Brightness sensor

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Location

The instrument cluster is located in the dashboard on the driver-side.

Task

The instrument cluster has the following tasks:

 Reading in of sensors, pickups and signals

 Evaluation of input factors

 Actuation of components

 Output of acoustic and information warnings

 Output of signals

Reading in of sensors, pickups and signals

The input factors are read in with the following connections:

 Interior CAN (CAN B)

 Engine compartment CAN (CAN C)

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Interior CAN

The signals are read in by the instrument cluster over the interior CAN.

The functions resulting therefrom are described in the corresponding function descriptions (see block diagram or function schematic).$

Engine compartment CAN

The signals are read in by the instrument cluster over the engine compartment 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.

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Component actuation

The instrument cluster directly actuates all internal actuators (e.g. indicator and warning lamps, stepper motors of displays, multifunction display) as well as the instrument illumination.

Output of acoustic and information warnings

To output the warning and information sounds requested by the systems installed in the vehicle, the instrument cluster actuates the internal speaker ("chime") or the warning buzzer (A1h1).

The "audible turn signal indicator " is realized by actuating the audible turn signal indicator (A1h2).

Output of signals

The signals are issued over the following connections:

 Interior CAN

 Engine compartment CAN

Interior CAN

The signals are sent by the instrument cluster over the interior CAN.

The functions resulting therefrom are described in the corresponding function descriptions (see block diagram or function schematic).$

Engine compartment CAN

The signals are sent by the instrument cluster over the engine compartment CAN.

The functions resulting therefrom are described in the corresponding function descriptions (see block diagram or function schematic).$