Ignition system function - GF07.10-P-1005MI
ENGINE 272.9 (except 272.982) in MODEL 204.0/2 as of model year 2009
ENGINE 272.9 (except 272.983) in MODEL 212
ENGINE 272.9 (except 272.984) in MODEL 207
ENGINE 272.9 in MODEL 204.9
ENGINE 273.9 in MODEL 207, 212
Function requirements for the ignition system, general points
- Circuit 87M ON (engine timing ON)
Ignition system, general points
A single-spark ignition coil is inserted directly into each cylinder. The ME-SFI [ME control unit (N310) reads in the following sensors and signals for the ignition system:
- knock sensor on the right (A16/1)
- knock sensor on the left (A16/2)
- hot film MAF sensor (B2/5), engine load
- intake air temperature sensor (B25b1)
- left and right intake camshaft Hall sensor (B6/4, B6/5), intake camshaft positions
- left and right exhaust camshaft Hall sensor (B6/6, B6/7), exhaust camshaft positions
- coolant temperature sensor (B11/4)
- pressure sensor (B28), intake manifold air pressure
- crankshaft Hall sensor (B70), engine speed and crankshaft position
The requirements of the torque coordination 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
- deceleration fuel shutoff
- transmission overload protection
- knock control
- torque coordination
Function sequence for ignition system
The ME-SFI [ME] control unit interrupts the respective ignition coil (T1) at the moment of the ignition timing at the ground end of the primary circuit to "circuit 1".
Determination of the ignition angle takes place dependent on a characteristics map according to the input signals from the ME-SFI [ME] control unit.
The ignition angles can be checked only with the Diagnosis Assistance System (DAS).
Engine configuration and firing order
| Electrical function schematic for ignition system | MODEL204 | PE07.10-P-2705-97FAB | |
| MODEL 207 | PE07.10-P-2705-97EAB | ||
| MODEL 212 | PE07.10-P-2705-97DAB | ||
| Overview of system components motor electronics (ME-SFI) fuel injection and ignition system | GF07.61-P-9997MI |