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Rpm signal check

Prepare the diagnostic equipment to download a voltage graph.

Select the VOLTMETER function from the INSTRUMENT menu with the time set at 5 seconds

Disconnect the connector for the control unit side sensor wiring and leave it disconnected.

Connect the probes between pins 1 and 2 of the sensor.

Press the START button on the diagnostic equipment to begin downloading a graph.

Let the engine be driven for at least 5 seconds and check that the breadth of the signal is more than 1.5 V and conforms to the graph enclosed.

- Replace the rpm sensor

   Op. 5510C26 ENGINE RPM SENSOR - R+R

- If the signal is OK, check the continuity/insulation of the wiring between the sensor and engine control unit.

- Check that the gap between the sensor and phonic wheel is between 0.5 and 1.5 mm. If not OK, restore the correct distance. If OK replace the engine control unit

   Op. 1056B82 INJECTION/IGNITION SYSTEM E.C.U. (ONE) - R + R