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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Engine Speed Sensor: Testing and Inspection

- Disconnect plug from EZ control unit.

EZ Control Unit Plug:

- Connect oscilloscope according to manufacturer's specifications.
Positive - terminal 7.
Negative - terminal 31d.

Engine Speed Sensor Signal:

- Crank engine. Should display above pattern.
- If voltage and engine speed signal are present, ignition coil must be triggered. If no engine speed signal is present, check resistance between terminals 7 and 31d. Should be 540 - 660 ohms.