Instrument cluster, component description

P54.30-7713-09

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

A1e16 Preglow indicator lamp
(on diesel engine)

A1p6 Electronic clock

A1p8 Electronic speedometer

A1p12 Gear indicator (with transmission 722)

A1p13 Multifunction display

A1p16 Transmission mode display
(with transmission 722)

A1r1 Instrument illumination variable resistor

A1s3 Trip odometer reset button

P Phototransistor

A1e17 ABS indicator lamp

A1e41 ESP warning lamp

A1e54 Coolant temperature warning lamp

A1e58 Engine diagnosis indicator lamp

A1e67 Low beam indicator lamp

A1p1 Coolant temperature gauge

A1p2 Fuel level and reserve indicator

A1p4 Ambient temperature display

A1p5 Tachograph

Location

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

Task

The instrument cluster is responsible for the display of operating conditions and convenience displays as well as for the edition of visual and acoustic indicator and warning messages.

The instrument cluster has the following tasks:

 Reading in of sensors, pickups and signals

 Evaluation of input factors

 Actuation of components

Reading in of sensors, pickups and signals

The instrument cluster reads in the input factors via the following connections:

 Interior CAN

 Engine compartment CAN

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Interior CAN

Input factors are read in by the following control units over the interior CAN:

- Radio (A2) (with code (523) MB Audio 20 radio)

- Radio and navigation unit (A2/56)
(with code (525) MB Audio 50 APS radio)

- COMAND operating, display and controller unit (A40/3)
(with code (527) COMAND APS with single DVD drive (with navigation system))

- Front SAM control unit with fuse and relay module (N10/1)

- Rear SAM control unit with fuse and relay module (N10/2)

- driver-side front seat adjustment control unit with memory (N32/1)
(with code (275) Memory package (driver seat, steering column, mirrors))

- Passenger-side front seat adjustment control unit with memory N32/2 (with code (242) Electrically adjustable front passenger seat with memory)

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- Left front door control unit (N69/1)

- Right front door control unit (N69/2)

- Overhead control panel control unit (N70)

- Upper control panel control unit (N72/1)

- EIS [EZS] control unit (N73)

- Steering column module (N80)

Engine compartment CAN

Input factors are read in by the following control units over the engine-compartment CAN:

- CDI control unit (N3/9) (on diesel engine)

- ME-SFI [ME] control unit (N3/10) (on gasoline engine)

- ETC [EGS] control unit (N15/3) (with transmission 722.6)

- ESP and BAS control unit (N47-5)

- Fully integrated transmission control unit (VGS) (Y3/8n4)
(with transmission 722.9)

- Electronic selector lever module control unit (N15/5)
(with transmission 722)

Evaluation of input factors

The read in input factors are evaluated by the instrument cluster's integrated processor and the corresponding components are actuated.

Component actuation

Components are actuated with the following lines:

 Direct line

Direct line

All the internal actuators (e.g. indicator and warning lamps, stepper motors and displays) are actuated directly by the instrument cluster.