Operation CHARM: Car repair manuals for everyone.
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

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Knock Sensor: Testing and Inspection








CIRCUIT DIAGRAM








HARNESS INSPECTION PROCEDURES

USING OSCILLOSCOPE





1. Connect the probe to the oscilloscope pick-up point as shown in the circuit diagram.
2. Rev up the engine to 5,000 rpm, and check the waveform.

TROUBLESHOOTING HINTS
If there is a problem with the knock sensor there will be a reduction in power.