Component description of ignition coil - GF15.10-P-2100SM

ENGINE 113.986

ENGINE 113.987

ENGINE 113.988

ENGINE 113.989

Fig 1: Identifying Ignition Coils - Engine 113.988

For each cylinder, a double ignition coil is fitted to the cylinder head cover.

Task

The ignition coils provide sufficient ignition power under all operating conditions for the respective ignition circuit (cylinder).

Design

The engine has two spark plugs (R4) per cylinder, which are actuated via a double ignition coil.

The double ignition coils have two separate ignition circuits, two sets of ignition wiring and a 3-pole plug connection.

Fig 2: Identifying Cylinder 1 To 8 Ignition Coils - Engine 113.988

Function

Fig 3: Ignition Coil Circuit Diagram - Engine 113.988

The ME control unit simultaneously actuates both primary windings of the double ignition coils at circuits 1a and 1b with ground.

The primary current flow is interrupted at the moment of ignition timing point. As a result of the sudden collapse of the magnetic field the ignition voltage is generated in the secondary windings.

The ignition voltages reach the spark plugs via the high-voltage connections "circuit 4a" and "circuit 4b".

Voltage is supplied to the double spark plugs via "circuit 15 fused".

Diodes are built-in to the secondary ignition to suppress additional ignition sparks when the primary current is switched on.

Because of the diodes, it is not possible to measure the resistance in the secondary windings.