2018 S-Class Presafe in action

In case of an imminent collision/accident, the car does the following -
1. The front head restraints adjust for optimum support.
2. If a rollover is possible, PRE-SAFE raises the windows and closes the sunroof.
3. Seatbelt tensioners act to snug the front seat belts.
4. Pink noise is emitted through the vehicle speakers to avoid any permeant hearing loss due to a loud sound.

Further, incase of a possible rear end collision, the car will flash hazard lights to alert driver of the incoming car, tighten the seat belts, pulling the occupants closer in the seats and increases the brake pressure to keep the car stationary (its its not moving).