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Ignition Signal

SPFI Ignition System Power Transistor:





PURPOSE
The ignition signal is used by the ECU to control the ignitor unit. This allows ignition triggering to be accomplished with a relatively low current signal from the ECU.

OPERATION
A signal is sent to the ignitor module whenever the engine is running. The signals are an on/off pulse, telling the ignitor when to fire the ignition coil.