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Home >> Saab >> 2005 >> 9-5 Linear, Automatic >> Repair and Diagnosis >> Electrical >> Gauges >> Main Instrument Unit >> Technical Description >> Tachometer >> Notes

Technical Description: Tachometer: Notes

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The main instrument is fitted with an electronic tachometer. The engine control module continuously sends information on the engine speed to the bus.

The tachometer is controlled by a stepper motor. The stepper motor is controlled by voltage pulses from the main instrument control module. At speeds below 1100 RPM (idling range), the display is "damped" to give a more stable speed display.

Fig 1: Tachometer Communication Diagram
G03871013Courtesy of SAAB-SCANIA OF AMERICA, INC.