Electronic Stability Program (Esp), Function

The "Electronic Stability Program" (ESP) is an active safety system which improves vehicle stability in all driving situations. It functions by applying braking force to one or more wheels on the front or rear axle. ESP stabilizes the vehicle when cornering, braking, or during non-driven coasting to keep it on the road and in the desired lane. ESP complements the familiar functions of the anti-lock brake system (ABS), acceleration slip regulation (ASR) and engine braking regulation (EBR). The stability regulation function is subordinate to the ABS and control systems. As well as actively intervening with the brakes, ESP also has an influence on engine/transmission management.

The Electronic Stability Program (ESP) includes the following system interplay.

• ABS prevents the wheels from locking when the brakes are applied so that the vehicle remains steerable and stable as it decelerates.
• ASR prevents the powered wheels from spinning when the vehicle is being driven. It also improves directional stability and road adhesion and increases traction potential across the entire vehicle speed range.
• EBR reduces brake slip at the drive wheels during deceleration and ensures directional control.
• ESP prevents the vehicle from breaking away when it is oversteered or understeered. In all situations it ensures that the vehicle does not deviate from the course specified by the driver (within the bounds of physical limits). Brake forces are produced selectively at the individual wheels to correct this.