Ignition Control Module: Description and Operation

PURPOSE
The Igniter physically fires the Ignition Coil in response to the engine control module's (ECM) signal.

CONSTRUCTION
The Igniter consists of a power transistor and circuitry to provide a tachometer output.

OPERATION
Computers generally produce low amperage signals as outputs, much lower than necessary to fire the Coil. The Igniter is essentially an electronic relay. It receives a "trigger" from the ECM and responds by turning a higher amperage current to the Ignition Coil on and off.