Electronic Accelerator Function - GF30.20-P-3015MNA
Engine 177.9 in model 205, 253
Engine 177.9 in model 213
up to model year 2021
Function requirements, general
- Engine runs
The ME-SFI [ME] control unit (N3/10) detects the engine running by evaluating the signals of the crankshaft Hall sensor (B70). The ME-SFI [ME] control unit directly reads in the signals of the crankshaft Hall sensor.
Electronic accelerator
The electronic accelerator function is integrated into the ME-SFI [ME] control unit and controls the engine torque in accordance with the driver command and operating conditions.
The ME-SFI [ME] control unit regulates the engine torque as a function of the following signals:
- Accelerator pedal position
- Service brake, status
- Engine torque requests (e.g. CRUISE CONTROL)
- Driving stage engaged
The accelerator pedal position is detected by the accelerator pedal sensor (B37). The ME-SFI [ME] control unit for model 205, 253 reads in the signals of the accelerator pedal sensor directly. With model 213, the powertrain control unit (N127) reads in the signals from the accelerator pedal sensor directly and sends these via the drive train CAN (CAN C1) to the ME-SFI [ME] control unit.
The Electronic Stability Program control unit (N30/4) sends the status of the service brake and engine torque requests of various systems via the chassis FlexRay (Flex E), powertrain control unit and drive train CAN to the ME-SFI [ME] control unit.
The fully integrated transmission control unit (Y3/8n4) sends information on the gear range engaged via the drive train CAN to the ME-SFI [ME] control unit.
The ME-SFI [ME] control unit also takes into account requests of the torque coordination function.
The ME-SFI [ME] control unit regulates the engine torque by:
- Adjusting the opening angles of the throttle valves
- Extending or shortening the injection duration of the fuel injectors
- Advancing or retarding the ignition angle. In this way, very rapid change of the engine torque is possible
The ME-SFI [ME] control unit actuates the following components for this purpose:
- Left throttle valve actuator (M16/60)
- Left throttle valve actuator motor (M16/60m1)
- Right throttle valve actuator (M16/61)
- Right throttle valve actuator motor (M16/61m1)
- Fuel injection system
- Cylinder 1 fuel injector (Y76/1)
- Cylinder 2 fuel injector (Y76/2)
- Cylinder 3 fuel injector (Y76/3)
- Cylinder 4 fuel injector (Y76/4)
- Cylinder 5 fuel injector (Y76/5)
- Cylinder 6 fuel injector (Y76/6)
- Cylinder 7 fuel injector (Y76/7)
- Cylinder 8 fuel injector (Y76/8)
- Ignition system
- Cylinder 1 +2 ignition coil (T4)
- Cylinder 1 ignition coil (T4t1)
- Cylinder 2 ignition coil (T4t2)
- Ignition coil, cylinders 3+4 (T4/1)
- Cylinder 3 ignition coil (T4/1t3)
- Cylinder 4 ignition coil (T4/1t4)
- Ignition coil, cylinders 5+6 (T4/2)
- Cylinder 5 ignition coil (T4/2t5)
- Cylinder 6 ignition coil (T4/2t6)
- Ignition coil, cylinders 7+8 (T4/3)
- Cylinder 7 ignition coil (T4/3t7)
- Cylinder 8 ignition coil (T4/3t8)
- Cylinder 1 +2 ignition coil (T4)
The engine torque is only determined by the accelerator pedal specification alone if no engine torque requests are active. The ME-SFI [ME] control unit ascertains the throttle valve positions via the following components:
- Left throttle valve actuator
- Actual value potentiometer 1, left (M16/60r1)
- Actual value potentiometer 2, left (M1 6/60r2)
- Right throttle valve actuator
- Actual value potentiometer 1, right (M16/61 r1)
- Actual value potentiometer 2, right (M16/61 r2)
Driveability and throttle change damping
Rapid accelerator pedal movements are not immediately translated into an engine torque. The engine torque is adapted to the request in a dampened manner. This avoids jolting in the drive train and improves ride comfort.
To do this, the ME-SFI [ME] control unit evaluates the signals from the following components:
- Accelerator pedal sensor
- Crankshaft Hall sensor
- Coolant temperature sensor (B11/4)
- Left oxygen sensor upstream of catalytic converter (G3/3)
- Left oxygen sensor sensor element upstream of CAT (G3/3b1)
- Right oxygen sensor upstream of catalytic converter (G3/4)
- Right oxygen sensor sensor element upstream of CAT (G3/4b1)
- Left oxygen sensor downstream of catalytic converter (G3/5)
- Left oxygen sensor sensor element downstream of CAT (G3/5b1)
- Right oxygen sensor downstream of catalytic converter (G3/6),
- Right oxygen sensor sensor element downstream of CAT (G3/6b1)
The ME-SFI [ME] control unit also takes the wheel speeds into account. The Electronic Stability Program control unit sends the wheel speeds via the chassis FlexRay, powertrain control unit and drive train CAN to the ME-SFI [ME] control unit.
Reverse travel
When driving in reverse, the ME-SFI [ME] control unit limits the engine torque to approx. 50 %. The fully integrated transmission control unit sends information on the gear range engaged via the drive train CAN to the ME-SFI [ME] control unit.
Adaptive accelerator pedal
The ME-SFI [ME] control unit changes the response time 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, are:
- Engine speed control
- Torque coordination
- Engine limp-home mode
| Electrical function schematic for electronic accelerator | Engine 177.9 in model 205, 253 | PE30.20-P-2050-97FBD | |
| Engine 177.9 in model 213 up to model year 2021 | PE30.20-P-2050-97DBG | ||
| Overview of system components for gasoline injection and ignition system with direct injection | Engine 177.9 in model 205, 253 | GF07.70-P-9998MNA | |
| Engine 177.9 in model 213 up to model year 2021 | GF07.70-P-9998MNE |