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Ignition Coil: Description and Operation



IGNITION COILS

Each ignition coil contains a solid state driver module as its primary element. The engine control module (ECM) signals the coil driver to initiate a firing event by applying ignition control (IC) circuit voltage for the appropriate time, or dwell. When the voltage is removed the coil fires the spark plug. The ignition coils use the following circuits:
- An ignition 1 voltage supply circuit
- An IC circuit
- Two ground circuits