ESP, function: Esp

The electronic stabilization program (ESP) is designed to stabilize the dynamic handling response of the vehicle by counteracting any tendency toward oversteer or understeer. The familiar functions of electronic brake force distribution, ABS, EDL and ASR (traction control) are incorporated in the system, but the characteristic function of the ESP is a controlled brake application at individual wheels.

Examples: 

In an oversteer condition the tail of the vehicle breaks out, and the vehicle rotates further about its vertical axis (rotational movement) than is required to maintain course through the corner. The system counteracts this excessive movement by applying a controlled braking force at the outside front wheel.

Fig 1: Identifying Oversteer Condition

Courtesy of AUDI OF AMERICA, INC.

In an understeer condition the front end of the vehicle does not follow the required cornering radius, and breaks away toward the outside of the corner. The vehicle does not rotate far enough about its vertical axis to maintain course through the corner. The system increases the amount of rotation by applying a controlled braking force at the inside rear wheel.

Fig 2: Identifying Understeer Condition

Courtesy of AUDI OF AMERICA, INC.

With the exception of the new components described below, the locations of the system components are the same as with the Bosch 5.3 system. The procedures for removing and installing components are described in:

See ANTILOCK BRAKE SYSTEM .