Ignition Coil: Description and Operation

Ignition Coils And Module:

Three separate coils are mounted to the module assembly. Each coil provides the spark for two plugs simultaneously. Coils can also be replaced separately.

Ignition Current Flow:

A "Waste Spark" method of distribution is used on this system. Each cylinder is paired with its opposing cylinder in firing order so that one cylinder on the compression stroke fires simultaneously with its opposing cylinder on the exhaust stroke. This process is reversed as the cylinders' roles are reversed.

The ignition module triggers the ignition coils individually. The Module receives signals from the camshaft and crankshaft position sensors, and from these signals, determines which coil is to fire first during engine cranking. The module then follows the firing order of the engine, which is predetermined.

The module grounds the ignition coils primary circuit, creating a magnetic field around the coil secondary windings. When spark is needed, the module opens the primary circuit, causing the magnetic field to collapse suddenly and induce high voltage in the secondary windings and through the secondary wires to the spark plugs.