(Electronic Accelerator Function - GF30.20-P-3015MMG)
ENGINE 276.8/9 in MODEL 166
up to Model Year 2016
Function requirements for the electronic accelerator, general points
- Circuit 87M (engine management ON)
- Engine runs
Electronic accelerator, general points
The electronic accelerator function is integrated into the ME-SFI [ME] control unit (N3/10) and controls the opening angle of the throttle valve dependent upon the driver input and the operating conditions.
The ME-SFI [ME] control unit regulates the throttle valve position according to the following sensors and signals:
- Accelerator pedal sensor (B37), accelerator pedal position
- Electronic Stability Program control unit (N30/4), brake actuation via chassis CAN 1 (CAN E1)
- Electronic Stability Program control unit cruise control request, via chassis CAN 1
- Video and radar sensor system control unit (N62/2) (for code 233 (DISTRONIC PLUS), for code 237 (Active Blind Spot Assist), for code 238 (Active Lane Keeping Assist), engine torque request via chassis CAN 1
- Fully integrated transmission control controller unit (Y3/8), gear range over drive train CAN (CAN C)
- Fully integrated transmission controller unit, reverse travel signal via the drive train CAN
The requirements of the torque coordination function are also taken into account.
Function sequence for electronic accelerator
The function sequence is described in the following steps:
- Function sequence for engine torque specification
- Function sequence for driveability functions
- Function sequence for reverse travel
- Function sequence for adaptive accelerator pedal
Function sequence for engine torque specification
The ME-SFI [ME] control unit controls the engine torque dependent on a characteristic map, dependent on the accelerator pedal sensor. To do this the ME-SFI [ME] control unit actuates the following components:
- Actuator motor (M16/6m1) in the throttle valve actuator (M16/6) by means of a pulse width modulated signal
- Ignition coils (T1) for regulation of the ignition angle efficiency over the ignition timing
- Fuel injectors (Y76) to regulate the lambda value over the fuel quantity
The engine torque is then only determined by the accelerator pedal position if no limited or increased torque requests from other functions or control units (e.g. cruise control request) are active. The actual value potentiometers 1 and 2 (M16/6r1, M16/6r2) report the current throttle valve position to the ME-SFI [ME] control unit.
The position feedback of the throttle valve actuator takes place by means of a contact-less angular sensor.
Function sequence for driveability functions
The driveability functions and throttle change damping have the task of limiting the change of engine torque as a result of a rapid movement of the accelerator pedal. The limitation serves to improve the ride comfort since jolting in the drivetrain is prevented.
The driveability functions and the throttle change damping take place on the basis of the following sensors and signals:
- Accelerator pedal sensor, accelerator pedal actuation (fast, slow)
- Coolant temperature sensor (B11/4)
- Pressure sensor downstream of throttle valve (B28/7), engine load
- Crankshaft Hall sensor (B70), engine RPM
- Left and right oxygen sensors upstream of catalytic converter (G3/3, G3/4)
- Left and right oxygen sensors downstream of catalytic converter (G3/5, G3/6)
- Electronic Stability Program control unit, wheel speed via chassis CAN 1
Function sequence for reverse travel
If the fully integrated transmission control controller unit sends the CAN signal "Reverse travel" over drive train CAN, the ME-SFI [ME] control unit restricts the engine torque to approx. 50 %. This optimizes ride comfort and driving safety when reversing.
Function sequence for adaptive accelerator pedal
The ME-SFI [ME] control unit changes the actuation characteristics of the accelerator pedal depending on the vehicle speed calculated from the wheel speed. At higher vehicle speeds a somewhat steeper accelerator pedal curve is used in order to improve the response time (reduction of the free travel).
Further functions which support the electronic accelerator and which are described in other documents:
- RPM control, function
- Torque coordination, function
- Engine limp-home mode, function
| Electrical function schematic for electronic accelerator | PE30.20-P-2050-97NAE | ||
| Overview of system components for gasoline injection and ignition system with direct injection | ENGINE 276.9 in MODEL 166 up to model year 2016 | GF07.70-P-9998MMG | |
| ENGINE 276.8 in MODEL 166 up to model year 2016 | GF07.70-P-9998MMU |