Ignition Coil/ICM Assembly

Each ignition control module (ICM) has the following circuits:

• An ignition voltage circuit
• A ground
• An ignition control (IC) circuit
• A low reference circuit

The powertrain control module (PCM) controls the individual coils by transmitting timing pulses on the IC circuit of each ignition coil/module to enable a spark event.

The spark plugs are connected to each coil by a short boot. The boot contains a spring that conducts the spark energy from the coil to the spark plug. The spark plug electrode is tipped with platinum for long wear and higher efficiency.