When Mercedes-Benz first unveiled PRE-SAFE® in 2002, the primary aim was to combat the problem of the invaluable seconds wasted just before an accident happens. PRE-SAFE® can use this time very effectively. The sensors at the heart of the ESP® and BAS Plus systems detect critical driving situations, such as heavy over- or understeer, critical steering movements, panic braking and emergency stops. In the S-Class, PRE-SAFE® is aided by the short-range sensors of DISTRONIC PLUS [1].

The PRE-SAFE® system evaluates this information and can initiate preventive measures in typical critical situations in order to protect the vehicle occupants. The front passenger seat can be moved into a more favourable crash position, the side windows and sliding sunroof can be closed, and the front seat belts tightened by the action of electric motors. In addition, the chambers in the side bolsters of the optional active multicontour seats[2] are filled with air, which improves lateral support in critical handling situations. This permits the sidebags, for example, to deploy their full protection potential.

The crash-responsive NECK-PRO head restraints are also part of the PRE-SAFE® concept. They can reduce the risk of whiplash injuries in the event of a rear-end collision, releasing in split-second a pre-tensioned spring that pushes the head restraints forwards and upwards, supporting the front seat occupants’ heads more swiftly.

In addition, the Brake Assist Plus system and the optional PRE-SAFE® Brake* can assist you. If the distance to a vehicle travelling ahead narrows down too fast, BAS Plus warns the driver by means of audible and visual signals, while it automatically calculates the brake pressure needed to reduce the impact speed and thus the severity of a possible collision. If the driver does not react, PRE-SAFE® can brake autonomously – first a partial application, then if a collision is unavoidable, a full brake application.