Computer Controlled Coil Ignition (C3I)

PURPOSE
The C3I ignition module monitors the camshaft sensor and the crankshaft sensor signals. This information is transmitted to the PCM which then controls ignition timing through the ignition module.

OPERATION
During cranking, the ignition module monitors the cam signal or "Sync Pulse" to begin the ignition firing sequence. Below 400 rpm, the module controls spark advance by triggering each of the three coil packs at a pre-determined interval based on engine speed only. Above 400 rpm, the PCM controls the spark timing (EST) and compensates for all driving conditions. The C3I module must receive a cam signal then a crank signal in than order to enable the engine to start.

DIAGNOSTIC NOTES:
The C3I module is not repairable. When a module is replaced, the coils must be transferred to the new module.