S07.10-0016-79
Block diagram |
A1/1 | Instrument cluster (KI) control unit | N3/34 | ME-SFI [ME] control unit | |
A16 | Knock sensor | N10/1 | Signal acquisition and actuation module (SAM) control unit | |
B2/8 | Hot film mass air flow sensor | N50 | Fuse and relay module control unit (SRM) | |
B6/15 | Intake camshaft position sensor | N93 | Central gateway (CGW) | |
B11/17 | Coolant temperature sensor | Y62 | Fuel injectors | |
B37/4 | Accelerator pedal module | CAN HMI | User interface CAN | |
B70/2 | Crankshaft Hall sensor | CAN V | Vehicle CAN | |
G1 | On-board electrical system battery | A | Mercedes-Benz | |
G3/1 | Oxygen sensor downstream of catalytic converter | B | Nissan | |
G3/2 | Oxygen sensor upstream of catalytic converter | C | Default | |
M16/6 | Throttle valve actuator | D | Optional |
Function requirements for injection regulation, general points
Circuit 87 ON (engine management ON)
Engine running.
Injection regulation, general points
The engine receives the fuel quantity required in each case from the ME-SFI control unit.
Using the characteristics map, the ME-SFI control unit calculates the injection duration and pressure based on the signals of the following sensors and devices:
Intake camshaft position sensor, intake camshaft position
Crankshaft Hall sensor, engine speed
Hot film mass air flow sensor
Coolant temperature sensor, coolant temperature
Oxygen sensor upstream of catalytic converter, residual oxygen
Oxygen sensor downstream of catalytic converter
Throttle valve actuator
Knock sensor
Atmospheric pressure sensor in ME-SFI [ME] control unit, atmospheric pressure for altitude adaptation
Accelerator pedal module, engine load request by driver, accelerator pedal operation fast or slow (when accelerating)
On-board electrical system battery
Instrument cluster (IC) control unit via central gateway (CGW)
Signal acquisition and actuation module (SAM) control unit
Fuse and relay module control unit (SRM)
Function sequence for injection regulation
The fuel quantity injected by the injection valve is controlled via a performance map in the ME-SFI control unit. The programmed value is specified by the engine operating conditions. These conditions are determined by the input signals (for engine speed and intake air) from the crankshaft Hall sensor, the intake camshaft position sensor and the hot film mass air flow sensor.
The ME-SFI [ME] control unit controls the injection period under the following operating conditions:
Function sequence for partial load and wide open throttle operation
Function sequence for acceleration
Function sequence for partial load and wide open throttle operation
In the ME-SFI control unit, the actuation time of the fuel injectors is calculated depending on the lambda control, the input signals from the hot film mass air flow sensor, and the requested engine torque.
Function sequence for acceleration
When there is rapid change in the accelerator pedal position, the throttle valve also opens and closes rapidly. This causes the mixture to become briefly leaner or too rich.
To prevent this, the ME-SFI [ME] control unit adapts the fuel/air mixture by lengthening or shortening the actuation time of the fuel injectors according to a characteristics map. This prevents jerking of the engine.