Electronic Accelerator, Location/Design/Function
Electronic Accelerator, Location/Design/Function
B37 Accelerator pedal sensor
R1 Set value potentiometer 1 (or Hall sensor 1)
r2 Set value potentiometer 2 (or Hall sensor 2)
M16/1 EA/CC/ISC [EFP/TPM/LLR] actuator (other designation:
M16/6 throttle valve actuator)
M1 Actuator motor
r1 Actual value potentiometer 1
r2 Actual value potentiometer 2
N3/10 ME-SFI control unit
The function of the electronic accelerator pedal EFP in the ME control unit determines the opening angle of the throttle valve over the actuator EFP/TPM/LLR (other designation: throttle valve actuator).
Further functions are:
- Idle speed control [ISC]
- Cruise control mode
- Variable speed limiter
- 30 km/hour limit
- Reduce/increase the engine torque for ASR/ESP operation
- short performance limitation, for example for a higher coolant temperature
- Emergency electronic accelerator pedal
- Safety concept
- Actuate indicator lamp EPC (up to 5/96)
- Storing faults
- Data exchanger via CAN
The opening angle of the throttle valve will only be determined by the accelerator pedal specification when no limiting functions are active.
The accelerator pedal position is detected by the set value potentiometer (B37r1) or Hall sensor in the pedal value sensor (B37) and information is released to the ME control unit (N3/10). In this way, the ME-SFI control unit determines the position of the throttle valve and actuates the throttle valve motor (M16/1m1).
The actual value potentiometer in the actuator (M16/1r1) signals the throttle valve position back to the ME-SFI control unit.
The second potentiometer in the actuator (M16/1r2) and the second signal from the pedal value sensor (potentiometer or Hall sensor) supplies a reference value for the plausibility check. In addition, the system switches over to the second potentiometer or the Hall sensor if the first potentiometer or Hall sensor fails (emergency mode).
Adaptative accelerator pedal (model 203, 209, 211, 215, 220, 230):
The engine control unit recognises how the accelerator pedal is being actuated and switches between characteristic curves. Eighty percent of the engine load is released for a pedal travel of about 50 % for a sporty driverer and about 40 % for a quiet driver. There is no further difference felt above a pedal travel of about 90 %.
Note: If, for example, the characteristic curve for a quiet driver is active after a long drive on the motorway then the accelerator pedal must be pressed down unusually hard to obtain a higher acceleration level.
Kickdown switch (S16/6)
The kickdown switch was no longer used from 9/01. Recognition of full load is now achieved over the signal from the pedal value sensor. The pressure point on the accelerator pedal before achieving the full load position remains.