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 Signal

ECU Pin Connectors:

To test the Engine Speed Signal to the ECU, locate pin A-5 on the ECU connector and test for the presence of an engine speed signal by connecting either a dwell meter or a tachometer. Either device will indicate the presence of a signal while the engine is running.

NOTE: To test pins do not remove the connector from the ECU, instead insert a straight pin or needle from the back side of the connector to access the pin.