Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

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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.