Ignition System: Description and Operation

DESCRIPTION AND OPERATION
The Electronic Ignition (EI) system consists of the following components:

Crankshaft Position (CKP) Sensor:

1. Crankshaft Position (CKP) sensor.

Ignition Control Module (ICM):

2. Ignition Control Module (ICM).

Two Four-Tower Coils:

3. Ignition coils (two four-tower).
4. The spark angle signal from the Powertrain Control Module (PCM).
5. Related wiring.

The EI (High Data Rate) System operates by sending crankshaft position information from the Crankshaft Position Sensor to the ICM. The ICM generates a Profile Ignition Pickup (PIP) signal and sends it to the PCM. The PCM sends a SPark OUTput (SPOUT) signal containing advance or retard timing information back to the ICM. The ICM processes the CKP and SPOUT signals and decides which coils to fire. In addition, the ICM generates an Ignition Diagnostic Monitor (IDM) signal to the PCM which is used to indicate a failure mode and also provide a tach output signal.