GF07.61-P-3008AM Motor Electronics (ME) Ignition System, Function
GF07.61-P-3008AM Motor Electronics (ME) Ignition System, Function
ENGINE 113.990 in MODEL 211, 219
ENGINE 113.991 in MODEL 215, 220
ENGINE 113.992 in MODEL 230 up to Model Year 2008
ENGINE 113.993 in MODEL 463 up to 31.5.12
ENGINE 113.995 in MODEL 230 up to Model Year 2008
A16/1 Knock sensor 1, right
A16/2 Left knock sensor 2
B6/1 Camshaft Hall sensor
B11/4 Coolant temperature sensor
B17/8 Charge air temperature sensor
B28 Pressure sensor (charge air)
B37 Accelerator pedal sensor
K40/4 Passenger-side fuse and relay module, (model 230)
K40/7 Right front fuse and relay module (model 215, 220)
L5 Crankshaft position sensor
M16/6 Throttle valve actuator
M16/7 Air recirculation flap actuator
N3/10 ME control unit
N10/1 Driver-side SAM control unit with fuse and relay module (model 211, 219)
N10/1 Front signal acquisition and actuation module (SAM) (model 463)
N15/3 EGS control unit
N47-5 ESP control unit (model 219)
N47-5 ESP and BAS control unit (model 463)
N47-5 ESP, SPS [PML] and BAS control unit (model 211, 215, 220, 230)
N73 EIS [EZS] control unit
R4 Spark plugs
T1/1- T1/8 - Cylinder 1 to 8 ignition coils
X11/4 Data link connector
a Cylinder 1 to 8 firing order
CAN CAN databus (Controller Area Network)
1 Determining the ignition angle and actuating ignition coils
The ME-SFI [ME] control unit evaluates basically the following input signals required to determine the ignition angle:
^ Crankshaft position,
^ Camshaft position,
^ Coolant temperature,
^ Charge air temperature,
^ Charge air pressure,
^ Knock signal,
^ Torque request via CAN
and interrupts at the ground end the ignition coil ignition coil primary circuit in the very ignition timing moment.
2 Ignition angle adaptation
2.1 Catalytic converter heating up (warming-up phase)
In addition to increasing the idle speed, the ignition angles are continuously retarded for about 20 s to bring the catalytic converters to operating temperature more quickly if:
^ Coolant temperature at start greater than -10 °C less than 40 °C
2.2 Idle
To assist idle speed control, the ignition angles can be retarded up to a crank angle of 36° or advanced up to a crank angle of 20.
Adjusting the ignition angle enables a faster response than adjusting the throttle valve.
2.3 Inertia fuel shutoff
To prevent a sudden increase in torque, the ignition angles are retarded briefly when combustion is resumed (when fuel injection valves are actuated).
2.4 Charge air/coolant temperature
To prevent the tendency to knock at increased charge air temperatures and coolant temperatures, depending on performance maps, the ignition angles are retarded at high load.
The ignition angle is retarded if:
^ Charge air temperature greater than 35 °C
^ Coolant temperature greater than 100 °C
2.5 Transmission overload protection
To protect shift elements of the automatic transmission from thermal overloads during power shifts (1-2, 2-1), the ignition angles are retarded briefly during the shift operation thereby reducing the engine torque. The ME control unit is supplied with a signal over the CAN databus by the ETC control unit for this purpose.
2.6 ESP/ASR control mode
To reduce engine torque in the ESP/ASR control mode as quickly as possible, the ignition angle is retarded before adjusting the throttle valve (reducing the opening angle). The information on the reduction in engine torque is transmitted by the ESP control unit to the ME-SFI [ME] control unit via the CAN data bus.
2.7 Smooth engine running analysis
Smooth engine running is constantly monitored in order to protect the catalytic converters from excessive thermal stresses if combustion misfiring exists.
If the smooth engine running analysis detects combustion misfiring, the appropriate fuel injector or injectors is/are no longer operated after a certain number of combustion misfirings.
2.8 Anti-knock control (AKC)
If uncontrolled combustion (knocking) occurs at one or several cylinders, the ignition angle at the relevant cylinder or cylinders is "Retarded".
2.9 Double ignition
Two spark plugs for each cylinder are beneficial because of the arrangement of the valves for achieving optimal emission levels and smooth engine running. Each spark plug is actuated separately via its own ignition coil by the ME control unit. Both ignition coils of a cylinder are combined to form a dual ignition coil.
Both ignition sparks of one cylinder are released simultaneously and always with optimal power.
The high voltage distribution is performed smoothly (i. e. without mechanical ignition distributor).
For troubleshooting in the double ignition system, it is possible to switch off one ignition circuit each with STAR DIAGNOSIS.
The ignition angles can be checked using STAR DIAGNOSIS.
