R 63 AMG (251.177) V8-6.3L (156.980) (2007)
Ignition Coil: Description and Operation
GF15.10-P-2100AMG Ignition Coil, Component Description
A dedicated ignition coil is plugged straight onto the spark plug (R4) for each cylinder.
Task
The ignition coils provide sufficient ignition energy under all operating conditions for the respective ignition circuit.
Function
An output stage is located in each ignition coil for the ignition coil primary circuit. The ME-SFI control unit (N3/10) actuates the ignition coil primary
circuit between connection (2) and (4). The current flow in the primary coil (P) causes a magnetic field to form. The dwell angle control determines the
operating time of the ignition coil primary circuit and thus the magnetic saturation of the ferrous core of the ignition coil.
The primary current flow is interrupted at the moment of ignition timing point. The sudden collapse of the magnetic field generates the ignition voltage
in the secondary coil (S), which is fed directly to the spark plugs (R4).
The diode (D) is fitted to suppress an additional ignition spark when the primary current is switched on.
Because of the diode it is not possible to measure the resistance of the secondary coil.
For diagnosis of the ignition coils, the primary current is measured. The capacitive tap is used to connect measuring equipment.