Ignition Coil: Description and Operation

Ignition Coil Secondary Circuit Test:

The Ignition Coil pack is located on the intake manifold and consists of 2 coils. The coils use the principle of mutual induction to step up battery (low) Voltage to ignition (high) Voltage. The Ignition Coil contains two windings of copper wire around a soft iron core. The primary winding is made of a hundred or so turns of wire. It is connected to the battery through the ignition switch. Current flows through it creating a magnetic field. When current flow in the primary winding is stopped (by the power transistor breaking the circuit ground), the collapse of the magnetic field causes a Voltage to be induced in the secondary windings. The ratio of turns in the primary windings to the number of turns in the secondary windings determines the Voltage step up.