Safety - at the heart of all our thinking


The Integral Safety Concept from Mercedes-Benz divides vehicle safety into four phases:

Virtually no other area inspires the Mercedes-Benz engineers to produce such consistently impressive results as much as research into new safety technologies. The first important safety milestone was reached back in the 1950s with the development of the passenger safety cell, invented by Béla Barényi. Today it is just one of many components of the Integral Safety Concept which edges Mercedes-Benz vehicles ever closer to our vision of accident-free driving.

Phase 1: safe driving

The majority of accidents start long before the actual collision: with a lapse in concentration, poor visibility or hazards which cannot be anticipated. That's why the Mercedes-Benz safety concept employs a range of measures to support safe driving in everyday operation and to help you bring critical situations under control.

360° camera (optional)[1]
DISTRONIC PLUS proximity control with STEER CONTROL (optional)[2]

DISTRONIC PLUS proximity control helps the driver to maintain a specified (timed) distance from the vehicle in front when travelling at speeds of 0 to 200 km/h.

When BAS PLUS Brake Assist is combined with the PRE-SAFE® brake system, rear-end collisions can be avoided more effectively. If radar sensors identify a potential collision and the driver applies the brake, BAS PLUS is primed to apply braking in accordance with the situation.

If a potential collision is identified above 30 km/h and the driver fails to apply the brakes sufficiently early, the PRE-SAFE® brake system emits visual and audible signals. If the driver does not respond to this warning, independent partial braking is activated approx. 1.6 seconds before the calculated impact at a deceleration rate of up to 4 m/s2. If the system categorises the situation as highly critical and there is still no reaction from the driver, an independent full brake application can be initiated automatically 0.6 seconds before what is considered an unavoidable impact.

Active Multicontour Seats (optional)[3]

The multicontour seats for driver and front passenger feature separately regulable air chambers which can be adapted to individual requirements. The seat side bolsters can adapt dynamically and automatically to the driving situation. Seat cushion depth, seat side bolsters and lumbar support can all be adjusted pneumatically.

Additional comfort is provided by a dynamic massage function in seven zones. This is one of many reasons why the Active Multicontour Seats were awarded the quality seal by the "Aktion gesunder Rücken e. V." ("Campaign for healthy backs"), which is awarded to products that are particularly "back friendly".

Active Parking Assist including PARKTRONIC (optional)[1]

The PARKTRONIC electronic parking aid monitors the front and rear of the vehicle when manoeuvring with the help of ten sensors and warns the driver if it detects a risk of collision. If the system identifies an obstruction, it emits a visual signal. As soon as the distance falls below approximately 35 centimetres, a short warning sound is emitted. If the vehicle gets even closer (to a distance of less than approximately 25 centimetres) a continuous signal is heard. PARKTRONIC uses this procedure to make parking easier, even with limited space available.

PARKTRONIC operates on the echo sounder principle. The electronic control unit uses ultrasonic signals received by sensors installed in front and rear bumpers to determine the distance between the obstacle and vehicle. Both the rear and front areas are monitored when reversing, but only the front when moving forwards.

As soon as an obstacle is detected within these areas, the visual and audible warnings are activated. As the vehicle approaches an obstacle in its path, the visual signals are the first to be activated. When the vehicle approaches an obstacle to less than around 30 or 35 centimetres audible warning is activated too, first sounding intermittently then, when a distance of 20 or 25 cm is reached, sounding continuously. The system is active below a speed of 16 km/h.

The ultrasonic parking aid does not relieve the driver of his responsibility for safety. The sensitivity of the sensors can be compromised if the ultrasonic signals encounter highly sound-absorbent surfaces (e.g. a bank of snow), for example. They may also fail to register objects located above or below the monitored area (e.g. a flower-box or trailer bar). The sensors must be free from dirt, ice and slush to operate correctly.

Active Lane Keeping Assist (optional)[2]

The Lane Keeping Assist feature can warn the driver, by means of a discreet vibration of the steering wheel, as soon as he unintentionally crosses a lane marking and thereby leaves the lane he is in.

If the vehicle is crossing a solid line and the driver does not react to the warning, braking can be applied to individual wheels as required. If the driver does not react, the brakes can be applied to individual wheels in a targeted manner to bring the car back into the right lane. However, if the indicator had been actuated or the steering wheel firmly turned, the system assumes that the lane change is intentional and does not react.

Active Blind Spot Assist (optional)[2]

Active Blind Spot Assist helps the driver to avoid potentially critical situations by monitoring the areas to the left and right of the vehicle when changing lane.

Close-proximity radar sensors monitor the difficult-to-see blind spot areas at speeds above 30 km/h. If the system detects another vehicle within monitoring range, a hazard warning triangle lights up in the corresponding exterior mirror.

If the driver then operates the indicator, an additional audible warning is sounded. This also happens if vehicles move from two lanes away into the lane alongside the driver. If the driver does not react to the warning signal, the system can automatically brake individual wheels in order to prevent a potential accident.

Anti-lock braking system (ABS)

The anti-lock braking system (ABS) enhances driving safety, especially in critical braking situations. When braking heavily, ABS reduces wheel locking by modulating the braking pressure for each wheel. This ensures that the vehicle remains directionally stable and can be steered while maintaining maximum braking power. In other words: ABS allows the driver to brake and steer simultaneously – allowing precise evasive manoeuvring – in order to avoid an accident.

Acceleration skid control (ASR)

The acceleration skid control (ASR) ensures that the wheels do not spin when accelerating. Especially when moving off on snow, ice and loose chippings, the acceleration skid control prevents individual wheels from spinning and the vehicle from sliding out to the side.

The system uses speed sensors to monitor the slip characteristics of the wheels. If the system senses a wheel is starting to spin, the acceleration skid control corrects the wheel speed by braking and intervening in the engine management system, thus reducing the wheel slip and wheel spin.


The ATTENTION ASSIST function is particularly helpful on long journeys and when driving at night; the system warns the driver if it detects signs of failing attention and increasing weariness.

At speeds of between 80 and 180 km/h, ATTENTION ASSIST warns the driver visually and audibly as soon as it registers any signs of drowsiness or inattention. The background: sensors analyse driving behaviour and can detect any changes compared with the previously determined individual driver profile.

Brake Assist (BAS)

Brake Assist (BAS) can protect against the risk of accidents. The system can recognise emergency braking from the speed at which the braking pedal is depressed and supply full braking power automatically.

The anti-lock braking system (ABS) then meters the braking power up to the slip threshold, which is how steering control is maintained. Once the driver releases the brake pedal, automatic brake boosting is immediately terminated.

ADAPTIVE BRAKE system with HOLD function

The standard-fit ADAPTIVE BRAKE system improves ride comfort and safety by helping to perform critical braking manoeuvres more safely with the basic function of the ABS anti-lock braking system, while convenience functions support the driver in everyday driving situations.

  • Supportive HOLD function: Activating the HOLD function of the ADAPTIVE BRAKE system by stepping on the brake pedal (depressing firmly) keeps the vehicle from rolling unintentionally when stopped at a light or in stop-and-go traffic.
  • Extra help: The Hill-Start Assist function prevents the vehicle from rolling back unexpectedly on inclines when moving from the brake to the accelerator pedal.
  • Full braking effect without delay: The "brake drying" function removes the film of water that forms on the brake discs in wet conditions.
  • For an even quicker response: With the "Priming" option, the brake linings on the brake discs are primed as soon as the driver takes his foot off the accelerator quickly.
COLLISION PREVENTION ASSIST collision warning including Adaptive Brake Assist
Electronic Stability Program ESP®

In critical situations, the Electronic Stability Program (ESP®) can help to stabilise the vehicle by applying a braking force to individual wheels, and adjusting engine performance. ESP® can for instance, reduce vehicle skidding by carrying out targeted braking interventions at individual wheels and prevent both over- and understeer, thus enhancing handling safety.

If the ESP® system detects a critical situation, it applies the brakes systematically to one or more wheels according to the situation. Should the system consider it necessary, it will also make an automatic adjustment to engine torque. In this way ESP® helps the driver to stabilise the vehicle within the laws of physics – particularly when cornering and during sudden evasive manoeuvres.

  • Central feature: The yaw-rate sensor continuously monitors vehicle movement around its vertical axis and compares actual values with the optimum value based on the driver’s steering movements and the vehicle’s speed. As soon as the vehicle deviates from the ideal line, ESP® intervenes by counteracting any swerving movements as soon as they occur.
  • Full traction at all times: Integrated acceleration skid control (ASR) also controls skidding by intervening in engine management.
  • Enhanced safety: As an integrated component of ESP®, ABS helps to prevent the wheels from locking and to maintain their steering function.
  • Additional features: ESP® supplements the functions of the anti-lock braking system (ABS) and acceleration skid control (ASR) by providing a driving stability function.
Reversing camera with dynamic guide lines in display (optional)

The reversing camera adds a convenient feature and also tangibly improves safety. The camera integrated in the boot lid transmits an image of the area behind the vehicle to the (optional) COMAND Online central multimedia system. The camera image not only makes parking easier but also aids in manoeuvring through difficult terrain.

Phase 2: in critical situations

Mercedes-Benz stands for automotive safety. That's why our vehicles support their passengers even in critical driving situations, so that every drive is a good one, if at all possible.

BAS PLUS Brake Assist with Cross-Traffic Assist and pedestrian protection (optional)[2]

The BAS PLUS Brake Assist system can help to prevent a rear-end collision or at least reduce the impact speed. With this system, two radar systems monitor the short, medium and long-range areas in front of the vehicle and detect objects up ahead. Their distance from the vehicle is calculated and the relative speed of the vehicles in front is determined compared with the vehicle's own speed.

If the system detects a severe shortening of the distance, such that a rear-end collision may occur, then the BAS PLUS Brake Assist system springs into action. The electronic system calculates the braking deceleration required to avert the accident. If the driver hits the brakes hard, BAS PLUS recognises this and automatically optimises the braking pressure needed to prevent an impact.

Depending on the car’s speed and its distance from the vehicle in front, BAS PLUS can either implement controlled braking or, if necessary, increase braking power up to maximum force. BAS PLUS engages only if the driver’s braking reaction is not sufficient to prevent an accident. BAS PLUS shuts off braking support if the driver stops braking or the radar no longer detects an object in front of the car. At the heart of the BAS PLUS Brake Assist system, which is available in conjunction with the optional DISTRONIC PLUS system, are sensors which monitor the area surrounding the vehicle, being able to detect potential dangers at lightning speed.

PRE-SAFE® occupant protection system

The preventive PRE-SAFE® occupant protection system can recognise critical driving situations and, if necessary, pre-emptively activate reversible safety systems to help reduce the risk of injury to the vehicle occupants.

This is based on PRE-SAFE® continuously monitoring sensor data from systems such as ESP® and BAS and identifying driving situations such as oversteer/understeer and emergency stops.

If the system identifies a typical critical driving situation, the electronic belt tensioners can be activated, the electrically adjustable front-passenger seat (only in conjunction with the Memory package) moved to a better position for impact, and the side windows and panoramic sliding sunroof (optional extra) automatically closed – all within fractions of a second.

PRE-SAFE® Brake[2]

If a potential collision is identified within the speed range 30 to 200 km/h and the driver fails to apply the brakes sufficiently early, the PRE-SAFE® brake system emits visual and audible signals.

If this warning goes unheeded, it initiates independent partial braking about 1.6 seconds before the estimated moment of impact at a deceleration rate of up to 4m/s2.

If the system assesses the situation as highly critical, and there is still no reaction from the driver, an independent full brake application can be initiated 0.6 seconds before the calculated moment of impact.

Phase 3: in an accident

Cars from Mercedes-Benz have a host of safety systems to prevent accidents. Should the worst come to the worst, however, a comprehensive range of occupant safety measures are activated. They include protection for the vehicle occupants as well as for other road users.

Airbags for driver and front passenger

The airbags for the driver and front passenger provide protection for the head and torso in a collision, and also afford additional stability to the entire body. They are thus able to mitigate the potential severity of injuries sustained in an accident. If the crash sensors detect a collision of a certain strength, the airbags are deployed.

The gas generators of both airbags can be activated in two stages. Both stages are activated depending on the braking force applied. Depending on the predicted severity of the impact, the first stage of the gas generator is initially activated and the airbag only partially filled. If a higher severity of impact is predicted, the second stage of the gas generator is activated after a slight delay and the airbag is completely filled.

Active bonnet[6]

The active bonnet can reduce the risk of injury to pedestrians and cyclists. If the system identifies a collision, the rear section of the active bonnet rises up by approximately five centimetres using spring force. This produces additional deformation space to intercept the impact with the upper body of the pedestrian earlier.

Kneebag for driver

The kneebag installed as standard on the driver’s side helps to protect the legs during impact and also stabilises the entire body. It can thus help mitigate the potential severity of injuries sustained in an accident. If the crash sensors detect a collision of a certain strength, the kneebag is deployed.

NECK-PRO head restraints on front seats

Activated in the event of a relevant rear-end collision, NECK-PRO head restraints for driver and front passenger can reduce the risk of sustaining a whiplash injury.

They ensure that the head receives support and the load on the spine is reduced at an earlier stage by employing a spring mechanism to move the head restraints forwards and upwards. The restraints can be pushed back to their original position by hand after their deployment.

Pelvisbags for driver and front passenger

The pelvisbags for the driver and front passenger provide protection for the pelvic region and hip in a collision. They are thus able to mitigate the severity of injuries sustained in an accident. If the crash sensors detect a relevant side collision, the pelvisbag is deployed.

The pelvisbag is deployed in the space between the front-seat occupants’ pelvic region and the door panelling. The pelvisbag then braces itself against the impact area, pushing the occupant’s pelvic region away from the door panelling at a very early stage of the collision.

Sidebags for driver and front passenger

The driver and co-driver sidebags provide protection to the side of the body in the event of a side impact, and also afford additional stability to the entire body. They are thus able to mitigate the severity of injuries sustained in an accident.

They are triggered when the central control unit and the side satellite sensors register acceleration or deceleration forces acting on the vehicle in excess of a certain threshold. The sidebags deploy at chest height between the vehicle side and the occupant.

Windowbags for driver and co-driver

In the event of a side impact with a force exceeding a defined threshold value (as well as other accidents with the corresponding lateral dynamics), the windowbag deploys to cover the side windows and reduce the risk of a collision between the passenger’s head and the side of the vehicle or of objects penetrating the vehicle interior. The windowbag is triggered simultaneously with the side- and pelvisbags and always on the side of the vehicle involved in the side impact.

When deployed, the windowbag spreads across the side windows between the A-pillar and C-pillar. The windowbag covers a large part of the surface area at the side.

The windowbag offers the following advantages:

  • Can help to protect the head area in the event of a side impact.
  • The design and large volume means that occupants are afforded an outstanding level of protection, regardless of their size.
  • Deployment between A and C-pillar means that protection is extended to rear passengers in the outer seats.
  • Reduces head movement in the event of a direct collision.
  • Can reduce penetration of fragments and other objects into the interior.

Phase 4: after an accident

To reduce consequential damage after an accident and support the work of the rescue services, a number of different actions are initiated, depending on the type and severity of the accident:

  • Best possible protection: the engine can be turned off automatically and the fuel supply can be cut off.
  • Eye-catching lighting: hazard and emergency interior lights can activate automatically to lower the risk of accidents and help locate the car.
  • Making escape easier: the door locking mechanism can be automatically released.
  • Better rescue possibilities: crash joints between the wing and the door can make opening the doors after a frontal collision easier.
  • Helpful connection: In the event of an accident or breakdown the Mercedes-Benz emergency call system (in conjunction with a connected mobile phone) can automatically contact an emergency call centre.

Mercedes-Benz has also published multilingual rescue guidelines (accessible worldwide on the internet) as a source of information for rescue services.

Rescue guidelines for emergency services (Daimler AG website)

[1] Available as individual option and as part of the optional Parking package. [2] Part of the optional Driving Assistance package Plus. [3] Part of the optional Active Multicontour Seat package. [4] Available as an individual option or as part of the optional Lane Tracking package. [5] Only available in conjunction with the optional COMAND Online multimedia system. [6] Not available for AMG models.