Slip Control (ASC/5)

Slip Control (ASC/5)












Traction Control will be standard equipment on both the 528i and 540i. A modified ASC/5 system will be used that operates essentially the same as the previous ASC/5 system. All of the hardware components remain the same as previous systems. The only change is a programming change to the system's control electronics.

A new feature has been added to the ASC/5 system for the E39 which improves stability control while driving through curves. As the vehicle enters a curve, the weight of the car shifts to the outside of the curve. Normally, if the driver brakes in this situation, an equal hydraulic force is applied to each wheel. Though the pressure is equal, the braking effort is unequal at the tire footprint due to the increased weight of the vehicle on the outside curve.

The new cornering stability feature regulates the apply pressure to the wheels based on the turning angle (curve recognition). If the driver brakes in the same situation, an unequal hydraulic pressure is applied to each side of the vehicle. Though the apply pressure is unequal, by compensating for the weight transfer in the turn, braking effort is equal at the tire footprint . The ASC control module monitors the speed signals from all four wheels to determine when this regulation is required.

This is a feature found on vehicles equipped with the Dynamic Stability Control system (DSC), however this ASC/5 system does not incorporate full DSC control.