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Ignition Control Module: Description and Operation

PURPOSE
The igniter is used as a control device for the ignition coil.
By modifying the pulse supplied to the igniter, the ECU is able to retard or advance ignition timing as conditions require.

LOCATION
Mounted on top of the transmission.

OPERATION
It is powered by ignition switch terminal Ign. 1 and receives power anytime the switch is turned ON. Based on the information provided by the TDC and CRANK sensors, the ECU pulses the signal to the igniter. Each time the igniter is pulsed, the ignition coil is signaled to send a spark to a spark plug. By modifying the pulse supplied to the igniter the ECU is able to retard or advance ignition timing as conditions require.