Ignition coils

Fig 1: Ignition Coils

Courtesy of VOLVO CARS OF NORTH AMERICA.

The ignition coils supply the spark plugs with high voltage to produce sparks. The engine control module (ECM) controls the ignition coils so that sparks are generated at the correct time.

Each ignition coil has its own integrated power stage.

The ignition coils are in the sparkplug wells above each spark plug.

The ignition coils for each cylinder have different terminals in the engine control module (ECM), depending on whether the engine has 5 or 6 cylinders.

The engine control module (ECM) can diagnose the ignition coils.