Ignition Control Module: Description and Operation

Typical Ignition Module Assembly:

PURPOSE
This DIS module monitors the crank sensor signals and based on these signals sends a reference signal to the ECM so that correct spark and fuel injector control can be maintained during all driving conditions.


OPERATION
During cranking, the DIS module monitors the "sync pulse" to begin the ignition firing sequence and below 400 rpm the module controls spark advance by triggering each of the three coils at a pre-determined interval based on engine speed only. Above 400 rpm the ECM controls the spark timing through the module (EST), and compensates for all driving conditions. The DIS module must receive a "sync pulse" and then a crank signal in that order to enable the engine to start. The DIS module is not repairable. When a module is replaced, the ignition coils must be transferred to the new module.