GF07.61-P-3008MOS Motor Electronics (ME) Ignition System, Function

GF07.61-P-3008MOS Motor Electronics (ME) Ignition System, Function
- as of model year 09


Function requirements for the ignition system, general points
^ Circuit 87M ON (engine control ON)

Ignition system, general points
Each cylinder has two spark plugs (R4). These are supplied with ignition voltage by the ECI ignition modules of the RH and LH cylinder banks (N92/1, N92/2). For the ignition system, the ME-SFI (N3/10) control unit reads the following sensors and signals:
- Front and rear knock sensor (left engine side) (A29/1, A29/2)
- Front and rear knock sensor (right engine side) (A30/1, A30/2)
- Camshaft Hall sensor, right cylinder bank (B6/3)
- Coolant temperature sensor (B11/4)
- Charge air temperature sensor (B17/8) and pressure sensor downstream of throttle valve actuator (B28/7), engine load
- Crankshaft position sensor (L5), engine speed and crankshaft position

The requirements of the engine torque requirement function are also taken into account.

For the following partial functions, ignition angle adjustment in the direction "retarded" or "advanced" takes place:
- Idle speed control
- Overheating / knock protection
- Inertia fuel shutoff
- Transmission overload protection
- Knock sensor system
- Engine torque request

Ignition system function sequence
At the ignition firing point, the ME-SFI control unit (N3/10) interrupts the primary circuit of the related cylinder at the ground end (at tml. 1) and thus actuates the output stages in the ECI ignition modules of the RH and LH cylinder banks. From the AC voltage, the output stages generate the ignition voltage for each spark plug.

Determination of the ignition angle takes place dependent on a performance map according to the input signals from the ME-SFI [ME] control unit.

Cylinder arrangement and ignition firing order

Diagnosis
The ignition angles can be checked only with the Diagnosis Assistance System (DAS).