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GF54.30-P-3021PM Engine RPM Display Function




GF54.30-P-3021PM Engine Rpm Display Function
- MODEL 203.0 /2 /7 as of 24.4.04 up to Model Year 8






A1 Instrument cluster
A1p5 Tachometer
L5 Crankshaft position sensor
N3/9 CDI control unit
N3/10 ME-SFI [ME] control unit

General
The coolant temperature gauge (A1p1) is located in the instrument cluster (A1) and is designed as an analog display. The display is driven by a stepper motor.

Networking:
- Engine speed is registered by the crankshaft position sensor (L5).
- The signals from the crankshaft position sensor (L5) are read in by the motor electronics control unit (N3/10) or by the CDI control unit (N3/9) and are placed on the Controller Area Network bus class C (engine compartment) (CAN-C).
- The instrument cluster (A1) receives this message and controls the stepper motor of the tachometer (A1p5) accordingly.

In the event of implausible or too high values the tachometer pointer are controlled to the end of the scale by the Controller Area Network bus class (engine compartment) (CAN-C) (A1p5). With no values from the CAN-C the tachometer pointer (A1p5) is controlled to the start of the scale. A fault message is also stored in the fault memory.

Adjustment for the number of cylinders
It is not necessary to adapt the tachometer (A1p5) to the number of cylinders in the engine.