Mercedes-Benz

Function of Active Brake Assist with cross-traffic function

Active Brake Assist with cross-traffic function consists of:

Distance warning function
Autonomous braking function
Situation-dependent braking assistance
Evasive Steering Assist

Active Brake Assist with cross-traffic function can help you to minimise the risk of a collision with vehicles or pedestrians, or reduce the effects of such a collision.

If Active Brake Assist with cross-traffic function detects that there is a risk of a collision, you will be warned visually and acoustically.

If you do not react to the visual or acoustic warning, autonomous braking can be initiated in critical situations.

In particularly critical situations, Active Brake Assist with cross-traffic function can initiate autonomous braking directly. In this case, the visual and acoustic warning occurs simultaneously with the braking application.

If you apply the brake yourself in a critical situation or apply the brake during autonomous braking, situation-dependent braking assistance occurs. The brake pressure increases up to maximum full-stop braking if necessary.

If the autonomous braking function or the situation-dependent braking assistance is triggered, additional preventive measures for occupant protection (PRE-SAFE®) may also be initiated, if the vehicle is equipped with these.

WARNING Risk of an accident if the detection of Active Brake Assist with cross-traffic function is impaired

Active Brake Assist with cross-traffic function cannot always recognise objects or complex traffic situations clearly.

In such cases, Active Brake Assist with cross-traffic function can:

Give a warning or brake without reason
Not give a warning or not brake

Always pay careful attention to the traffic situation and do not rely entirely on Active Brake Assist with cross-traffic function.

Be prepared to brake or swerve if necessary.

Also observe the system limitations of Active Brake Assist with cross-traffic function.

The individual subfunctions are available in the following speed ranges:

Distance warning function

The distance warning function issues a warning at speeds:

From approximately 30 km/h, if over several seconds the distance maintained to the vehicle travelling in front is insufficient for the driven speed. The distance warning lamp then lights up in the instrument cluster.
From approximately 7 km/h, if your vehicle is critically close to a vehicle or pedestrian. An intermittent warning tone sounds and the distance warning lamp lights up in the instrument cluster .

Brake immediately or take evasive action, provided it is safe to do so.

The distance warning function can aid you in the following situations with an intermittent warning tone and a warning lamp:

Speeds up to approximately 250 km/h when approaching vehicles ahead.
Speeds up to approximately 100 km/h when approaching stationary vehicles.
Speeds up to approximately 70 km/h when approaching pedestrians who are standing still or crossing, or crossing vehicles.

Autonomous braking function

If the vehicle is travelling at speeds above approximately 7 km/h, the autonomous braking function may intervene in the following situations:

Speeds up to approximately 250 km/h when approaching vehicles ahead.
Speeds up to approximately 100 km/h when approaching stationary vehicles.
Speeds up to approximately 70 km/h when approaching pedestrians who are standing still or crossing, or crossing vehicles.

Situation-dependent braking assistance

The situation-dependent braking assistance can intervene from a speed of approximately 7 km/h in the following situations:

Speeds up to approximately 250 km/h when approaching vehicles ahead.
Speeds up to approximately 100 km/h when approaching stationary obstacles.
Speeds up to approximately 70 km/h when approaching pedestrians who are standing still or crossing, or crossing vehicles.

Cancelling a brake application initiated by Active Brake Assist with cross-traffic function

You can stop a brake application initiated by Active Brake Assist with cross-traffic function at any time by:

Depressing the accelerator pedal fully or kickdown.

If at least one of the following conditions is fulfilled, Active Brake Assist with cross-traffic function will cancel the brake application:

You manoeuvre to avoid the obstacle.
There is no longer a risk of collision.
An obstacle is no longer detected in front of your vehicle.

Evasive Steering Assist

Evasive Steering Assist has the following characteristics:

Can detect stationary or crossing pedestrians.
Can assist the driver with additional steering assistance if it detects a swerving manoeuvre.
Can be activated by an abrupt steering movement during a swerving manoeuvre.
Can assist during swerving and straightening of the vehicle.
Can react from a speed of approximately 20 km/h up to a speed of approximately 70 km/h.

You can prevent the assistance at any time by active steering.

WARNING Risk of an accident despite Evasive Steering Assist

Evasive Steering Assist cannot always clearly identify objects and complex traffic situations.

In addition, the steering support of Evasive Steering Assist is generally not sufficient to avoid a collision.

In such cases Evasive Steering Assist can:

give an unnecessary warning or provide assistance
not give a warning or not provide assistance

Always pay careful attention to the traffic situation; do not rely on Evasive Steering Assist alone.

Be ready to brake and take evasive action, if necessary.

Prevent the assistance by actively steering in non-critical driving situations.

Drive at an appropriate speed if pedestrians are close to the path of your vehicle.

Also observe the system limitations of Evasive Steering Assist.

System limitations

Active Brake Assist with cross-traffic function may be impaired or may not function in the following situations:

In snow, rain, fog, heavy spray, if there is glare, in direct sunlight or in greatly varying light conditions.
If the sensors are dirty, misted up, damaged or covered.
If the sensors malfunction due to other radar source interference, for example strong radar reflections in multi-storey car parks.
If a loss of tyre pressure or a defective tyre has been detected and displayed.

The system may not react correctly:

In complex traffic stations where objects cannot always be clearly identified.
To pedestrians or vehicles if they move quickly into the sensor detection range.
To pedestrians who are hidden by other objects.
If the typical outline of a pedestrian cannot be distinguished from the background.
If a pedestrian is not recognised as such, e.g. due to special clothing or other objects.
On bends with a tight radius.