Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

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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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Ignition Timing Control

DESCRIPTION AND OPERATION
By stopping/flowing the primary current in the ignition coil through ON/OFF control of the ignition power transistor provided in the ignition primary circuit, the ignition timing is controlled so that ignition may take place at the most appropriate time for the operating condition of the engine.

The ignition timing is determined by the ECM in accordance with the engine speed, intake air quantity, engine coolant temperature, etc.