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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Measurement Method




1. Disconnect the connector of the ignition power transistor, and connect the special tool (harness connector: MB991348) between the disconnected ends. (Connect all terminals.)




2. Connect the primary pickup of the analyzer to the terminal No. 3 of the ignition power transistor connector.
3. Connect the ground terminal of the primary pickup.
4. Clamp the spark plug cable with the trigger pickup.


NOTE: The waveform of the cylinder clamped with the trigger pickup will displayed on the left end of the screen.