Electronic Accelerator Function - GF30.20-P-3015MNL

Engine 176.9, 177.9 in model 217 

Engine 176.9, 177.9 in model 222 

Engine 177.9 in model 290 

up to model year 2021 

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 in the ME-SFI [ME] control unit (N3/10) and controls the engine torque depending on the driver command and the operating conditions.

The ME-SFI [ME] control unit regulates the engine torque, dependent on the following signals:

• Accelerator pedal sensor (B37), accelerator pedal position
• Electronic Stability Program control unit (N30/4), brake actuation, cruise control requests and engine torque requests via the suspension FlexRay (Flex E), powertrain control unit (N127), and drive CAN (CAN C1)
• Mercedes-Benz Intelligent Drive control unit (N62/4) (with code 23P (Driving Assistance Package)), engine torque request (increasing or reducing) via drive CAN, powertrain control unit, suspension FlexRay
• Fully integrated transmission control unit (Y3/8n4) (model 217, 222), drive range and reversing signal via drive CAN
• Fully integrated transmission control electric controller unit control unit (Y3/8n4) (model 290), drive range and reversing signal via the drive 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 actuates 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 assembly parts:

• Left and right throttle valve actuator motors (M16/60m1, M16/61m1) in the left and right throttle valve actuators (M16/60, M16/61) over a pulse width modulated signal
• Ignition coils for cylinder 1+2 to 7+8 (T4 to T4/3) for regulation of the ignition angle effectiveness over the firing point
• Cylinder 1 to 8 fuel injectors (Y76/1 to Y76/8) for regulation of the lambda value over the fuel quantity

Engine torque is only determined by the accelerator pedal position alone if no limiting or increasing engine torque requests from other functions or control units (e.g. cruise control request) are active. The left and right actual value potentiometers 1 and 2 (M16/60r1, M16/60r2, M16/61r1, M16/61r2) signal the current throttle valve position to the ME-SFI control unit.

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 signals:

• Accelerator pedal sensor, accelerator pedal actuation (fast, slow)
• Crankshaft Hall sensor (B70), engine speed
• Coolant temperature sensor (B11/4), coolant temperature
• Oxygen sensor elements at left and right upstream of catalytic converter (G3/3b1, G3/4b1), oxygen and nitrogen concentration level
• Oxygen sensor elements at left and right downstream of catalytic converter (G3/5b1, G3/6b1), oxygen and nitrogen concentration level
• Electronic Stability Program control unit, wheel speed via the suspension FlexRay, powertrain control unit, and drive CAN

Function sequence for reverse travel 

If the fully integrated transmission control unit (model 217, 222) or the fully integrated transmission control controller unit control unit (model 290) transmits the "reversing" CAN signal via the drive CAN, the ME-SFI control unit limits the engine torque to approx. 50 %. This optimizes ride comfort and driving safety in reverse travel

Function sequence for 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 slightly steeper accelerator pedal curve is used in order to improve the response time (reduction of 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 290 up to model year 2021	PE30.20-P-2050-97XBA
		Engine 176.9, 177.9 in model 217. Engine 176.9, 177.9 in model 222	PE30.20-P-2050-97SEL
	Overview of system components for gasoline injection and ignition system with direct injection		GF07.70-P-9998MNL