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

ENGINE 281.910 in MODEL 453.0/3/4 

Function requirements for the electronic accelerator, general points 

• Circuit 87 (Engine management ON)
• Engine runs
• Throttle valve actuator (M16/6) adjusts itself for "ignition On"

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, dependent on the following signals:

• Accelerator pedal sensor (B37), accelerator pedal position
• DKG control unit (N15/13) (for code 429 (twinamic)), gear range via drive train CAN (CAN C)
• DKG control unit (for code 429 (twinamic)), reverse travel signal via the drive train CAN
• Brake lights switch (S9/1), status over the center SAM control unit (N10/10) and interior CAN (CAN B)
• Start enable clutch pedal switch (S40/3), (for code 410 (5-speed manual transmission)), clutch operation
• CC/variable speed limiter switch (S40/4s6), CC requirements over steering wheel clock spring contact (A45/1)

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 throttle valve control 
• Function sequence for throttle valve damping 

Function sequence for throttle valve control 

Depending on the accelerator pedal sensor, the ME-SFI [ME] control unit actuates the throttle valve actuator according to a characteristics map.

To do this, the ME-SFI [ME] control unit actuates the actuator motor (M16/6m1) in the throttle valve actuator by means of a pulse width modulated signal (PWM signal). Provided there are no limiting functions active (for example, cruise control request), the opening angle of the throttle valve is determined by the accelerator pedal position alone. The actual value potentiometer 1 (M16/6r1) and actual value potentiometer 2 (M16/6r2) report the current throttle valve position to the ME-SFI [ME] control unit.

Function sequence for throttle valve damping 

The ME-SFI [ME] control unit controls the throttle valve damping according to the following sensors and signals:

• Accelerator pedal sensor, accelerator pedal actuation (rapid, slow), e.g. temporal change in the accelerator pedal position
• Crankshaft position sensor (L5), engine speed
• Coolant temperature sensor (B11/4)
• Throttle valve actuator, throttle valve position

The task of throttle valve damping is to delay closing of the throttle valve down to idle speed range if the accelerator is suddenly released. In this way, the engine torque reduces slowly and the vehicle does not slow down with jerks.

Further functions which support the electronic accelerator and which are described in other documents are:

• Rpm control
• Cruise control
• Torque coordination
• Engine limp-home mode

	Electrical function schematic for electronic accelerator		PE30.20-P-2050-97BBA
	Overview of system components motor electronics (ME-SFI) fuel injection and ignition system		GF07.61-P-9997KJ