Operation CHARM: Car repair manuals for everyone.

Ignition Control Module: Description and Operation


The Igniter, located near the coil on the left side of the engine compartment, is a switching device that activates the primary ignition coil circuit. The ECU determines optimum ignition timing from various inputs and transmits a primary current "OFF" signal to the igniter to control ignition timing.

The ECU calculates input from these devices to control ignition timing:

Distributor Ne signal
Distributor G signal
Water thermosensor
Airflow meter
Throttle sensor/idle switch
Inhibitor switch (A/T)
A/C switch
EGR position sensor
Test connector (for base timing adjustment)