Oscilloscope Patterns and Waveforms

INSPECTION USING OSCILLOSCOPE
- With the engine racing (4,000 rpm) measure between terminals KNKR, KNKL 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 141 per sec. (Normal mode vibration frequency of knock sensor: 7.1 KHz).




HINT: If normal mode vibration frequency is not 7.1 KHz, the sensor is malfunctioning.