ASR V/ESP Drive Moment Control Circuit

Acceleration Slip Regulation (ASR)
A drive moment control must take place in order to achieve optimum traction when the drive moment is too high (spinning wheels). The drive moment reduction is controlled by an exchange of data between the control module of the ASR (N47-1) or ESP, SPS and BAS control module (N47-5) traction system installed and the respective control module of the injection and ignition system via the CAN data bus. On the gasoline engine these are the control modules: EA(N4/1), LH-SFI (N3/1, N3/2, N313), HFM-SFI (N3/4) or ME-SFI (N3/10, N3/11, N3/12) and on the diesel engine the IFI control module (N3/7), DFI control module (N3/8) or CDI control module (N3/9).

^ 4-Cylinder Gasoline Engine With Compressor, 6 - 8 - And 12 Cylinder Gasoline Engine:
The throttle valve position of the throttle actuator (M16/1 or M16/6) is reduced by the EA (N4/1) or ME-SFI (N3/10, N3/11, N3/12) control module relative to the accelerator pedal position applied by the driver and the ignition timing is retarded by the engine control module (HFM-SFI) (N3/4), ME-SFI (N3/10, N3/11, N3/12) or the LH-SFI control module (N3/1).

^ 4-Cylinder Gasoline Engine Without Compressor:
The fuel supply is shut off by the engine control module (HFM-SFI) (N3/4).

^ Diesel Engine:
The fuel quantity is reduced by the IFI control module (N3/7),
DFI control module (N3/8) or CDI control module (N3/9),
A check is constantly made in the ASR or ESP control module (N47-1 or N47-5) as to whether the control functions can be cancelled e.g. as a result of a sudden improvement in road surface adhesion, so that the drive moment applied by the driver via the accelerator pedal can come back into operation again as soon as possible.

Engine Braking Regulation (EBR)
(Not On 4-Cylinder Gasoline Engine Without Compressor)
If Slip Occurs At The Drive Wheels When The Throttle is closed, this is also recognized by the ASR or ESP control module (N47-1 or N47-5).

^ 4-Cylinder Gasoline Engine With Compressor, 6, 8 And 12 Cylinder Gasoline Engine:
The signal (throttle valve increase) is transmitted to the EA control module (N4/1) or ME-SFI control module (N3/10, N3/11, N3/12). The calculated throttle valve opening is controlled by the control module (N4/1, N3/10, N3/11, N3/12) via the EA/CC/ISC actuator (M16/1).

^ Diesel Engine:
The signal (fuel quantity increase) is transmitted to the IFI control module (N3/7) or DFI control module (N3/8). The quantity of fuel injected is increased by the control module.
Using this information, the drive moment can be changed so that no slip occurs at the drive wheels, thereby stabilizing the lateral control of the vehicle. This process takes place without informing the driver (ASR warning lamp A1e21).