Ignition Control Module: Description and Operation

The Igniter, located near the coil on the left inner fender, 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
^ Water thermosensor
^ Airflow sensor
^ Idle switch
^ Ignition switch ("START" position)
^ Test connector (for base timing adjustment)