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Oscilloscope Patterns and Waveforms

Reference INSPECTION USING OSCILLOSCOPE

- With the engine racing (4,000 rpm) measure waveform between terminals KNK1, KNK2 of ECM and body ground.

HINT: The correct waveform is as shown.

- Spread the time on the horizontal axis and confirm that period of the wave is 123 m sec. (Normal mode vibration frequency of knock sensor: 8.1 KHz).

HINT: If normal mode vibration frequency is not 8.1 KHz, the sensor is malfunctioning.