Collision prevention assist

General notes

COLLISION PREVENTION ASSIST consists of Adaptive Brake Assist and the distance warning function, which are described in the following.

Distance warning function

Important safety notes

Observe the "Important safety notes" section  .

WARNING

The distance warning function does not react: • to people or animals • to oncoming vehicles • to crossing traffic • when cornering Thus, the distance warning function cannot provide a warning in all critical situations.

There is a risk of an accident.

Always pay careful attention to the traffic situation and be ready to brake.

The distance warning function cannot always clearly identify objects and complex traffic situations.

In such cases, the distance warning function may:
• give an unnecessary warning • not give a warning Always pay careful attention to the traffic situation and do not rely solely on the distance warning function.

Function

■ To activate/deactivate: activate or deactivate the distance warning function in the on-board computer  .

When the distance warning function is activated, the multifunction display shows the symbol, as long as the HOLD
function is not switched on  . On vehicles with Active Parking Assist, the symbol is displayed when P is
engaged or you are driving faster than 22 mph (35 km/h).

The distance warning function can help you to minimize the risk of a front-end collision with a vehicle ahead or reduce the effects of such a collision. If the distance warning function detects that there is a risk of a collision, you will be warned visually and acoustically. The distance warning function cannot prevent a collision without your intervention.

Starting at a speed of around 20 mph (30 km/h), this function warns you if you rapidly approach a vehicle in front. An intermittent warning tone will then sound and the distance warning lamp will
light up in the instrument cluster.

■ Brake immediately in order to increase the distance from the vehicle in front.

or
■ Take evasive action, provided it is safe to do so.

For the distance warning function to assist you when driving, the function must be activated in the on-board computer and be operational  .

Due to the nature of the system, particularly complicated driving conditions may cause the system to display unnecessary warnings.

With the help of the radar sensor system, the distance warning function can detect obstacles that are in the path of your vehicle for an extended period of time.

At speeds up to 40 mph (70 km/h), the distance warning function may also detect stationary obstacles, for example stopped or parked vehicles.

If you approach an obstacle and the distance warning function detects a risk of a collision, the system will initially alert you both visually and acoustically.

In particular, the detection of obstacles can be impaired if:
• there is dirt on the sensors or anything else covering the sensors
• snow or heavy rain • interference by other radar sources • there are strong radar reflections, for example in parking garages • a narrow vehicle traveling in front, e.g. a motorbike
• a vehicle traveling in front on a different line relative to the center of your vehicle Following damage to the front end of the vehicle, have the configuration and operation of the radar sensor checked at a qualified specialist workshop. This also applies to collisions at low speeds where there is no visible damage to the front of the vehicle.

Adaptive Brake Assist

Observe the "Important safety notes" section  .

WARNING

Adaptive Brake Assist cannot always clearly identify objects and complex traffic situations. In these cases, Adaptive Brake Assist may not intervene. There is a risk of an accident.

Always pay careful attention to the traffic situation and be ready to brake.

WARNING

Adaptive Brake Assist does not react:

• to people or animals • to oncoming vehicles • to crossing traffic • to stationary obstacles • when cornering

As a result, Adaptive Brake Assist may not intervene in all critical conditions. There is a risk of an accident.

Always pay careful attention to the traffic situation and be ready to brake.

Adaptive Brake Assist provides braking assistance in hazardous situations at speeds greater than 20 mph (30 km/h) and uses radar sensor technology to assess the traffic situation.

With the help of Adaptive Brake Assist, the distance warning signal can detect obstacles that are in the path of your vehicle for an extended period of time.

Should you approach an obstacle and Adaptive Brake Assist has detected a risk of collision, Adaptive Brake Assist calculates the braking force necessary to avoid a rear-end collision. Should you apply the brakes vigorously, Adaptive Brake Assist will automatically increase the braking force to a level suitable for the traffic conditions.

■ Keep the brake pedal depressed until the emergency braking situation is over.

ABS prevents the wheels from locking.

The brakes will work normally again if: • you release the brake pedal.

• there is no longer any danger of a rear-end collision.

• no obstacle is detected in front of your vehicle.

Adaptive Brake Assist is then deactivated.

If Adaptive Brake Assist requires particularly high brake pressure, preventive passenger protection measures (PRE-SAFE®) are deployed simultaneously.

Up to vehicle speeds of around 155 mph (250 km/h), adaptive Brake Assist is capable of reacting to moving objects that have already been recognized as such at least once over the period of observation. Adaptive Brake Assist does not react to stationary obstacles.

If Adaptive Brake Assist is not available due to a malfunction in the radar sensor system, the brake system remains available with full brake boosting effect and BAS.

In particular, the detection of obstacles can be impaired if there is:

• dirt on the sensors or anything else covering the sensors
• snow or heavy rain • interference by other radar sources • there are strong radar reflections, for example in parking garages • a narrow vehicle traveling in front, e.g. a motorbike
• a vehicle traveling in front on a different line relative to the center of your vehicle

Following damage to the front end of the vehicle, have the configuration and operation of the radar sensor checked at a qualified specialist workshop. This also applies to collisions at low speeds where there is no visible damage to the front of the vehicle.