ASR drive torque control circuit, function - GF42.40-P-2100SK

MODEL 171.4 

Acceleration slip regulation (ASR) 

In order to achieve optimum traction for a too large drive torque (spinning wheels), the drive torque must be controlled. The drive torque reduction is controlled by the data exchange between the ESP and BAS control unit (N47-5) and the respective control unit of the injection and ignition system via the Controller Area Network- Bus class C (engine compartment) (CAN-C). The motor electronics control unit (N3/10) reduces the throttle valve position via the throttle valve actuator (M16/6) compared with the accelerator pedal position specified by the driver as well as the ignition timing retarded. In the ESP and BAS control unit (N47-5) it is constantly checked whether the control functions can be canceled as a result of a sudden improvement in road adhesion. So the drive torque specified by the driver via the accelerator pedal can be permitted again in good time.

Engine braking regulation control (MSR) 

If slip occurs at the drive wheels when the throttle is released, this is detected by the ESP and BAS control unit (N47-5). The signal (throttle valve position) is reported to the motor electronics control unit (N3/10) via CAN C. The calculated throttle valve opening (N3/10) is controlled via the throttle valve actuator (M16/6).

Using this information the drive torque can be varied so that no slip occurs at the drive wheels. This improves the lateral stability of the vehicle. This process takes place without informing the driver (ESP warning lamp (A1e41).