Active Lane Keeping Assist monitors the area in front of your vehicle by means of multifunction camera 
. It serves to protect you against unintentionally leaving your lane. You will be warned by means of a vibration in the steering wheel and a course-correcting brake application guides you back into your lane.
Active Lane Keeping Assist detects lane markings.
A front wheel passes over the lane markings.
Active Lane Keeping Assist detects lane markings on both sides.
A front wheel drives over a solid lane marking.
Whether a warning is issued and when this occurs also depends on the selected sensitivity setting (standard or adaptive).
If you fail to adapt your driving style, Active Lane Keeping Assist can neither reduce the risk of an accident nor override the laws of physics. It cannot take into account road, weather or traffic conditions. Active Lane Keeping Assist is only an aid. You are responsible for the distance to the vehicle in front, for vehicle speed, for braking in good time and for staying in lane.
Vehicles with Lane Tracking package: if the lane markings are solid lines and you do not react to the warning, a lane-correcting brake application can bring the vehicle back into the original lane.
Vehicles with Driving Assistance package or Driving Assistance Plus package: if you do not react to the warning, a lane-correcting brake application can bring the vehicle back into the original lane. In the case of a broken lane marking being detected, a brake application will only be made if a vehicle has been detected in the adjacent lane. Oncoming vehicles, overtaking vehicles and vehicles in adjacent lanes can be detected.
The brake application is available in the speed range between 60 km/h and 200 km/h.
If a lane-correcting brake application occurs, display appears in the multifunction display.
You clearly and actively steer, brake or accelerate.
You have switched on the turn signal indicator.
A driving safety system intervenes, such as ESP®, Active Brake Assist or Active Blind Spot Assist.
You have adopted a sporty driving style with high cornering speeds or high rates of acceleration.
ESP® is deactivated.
When driving with a trailer, the electrical connection to the trailer has been correctly established.
If a loss of tyre pressure or a defective tyre has been detected and displayed.
If there is poor visibility, e.g. due to insufficient illumination of the road, highly variable shade conditions, or due to rain, snow, fog or heavy spray.
If there is glare, e.g. from oncoming traffic, the sun or reflections.
If there is dirt on the windscreen in the vicinity of the multifunction camera or the camera is misted up, damaged or obscured.
If no or several, unclear lane markings are present for one lane, e.g. near roadworks.
If the lane markings are worn, dark or covered.
If the distance to the vehicle in front is too small and the lane markings thus cannot be detected.
If the lane markings change quickly, e.g. lanes branch off, cross one another or merge.
If the carriageway is very narrow and winding.
Vehicles with Driving Assistance package or Driving Assistance Plus package: Active Lane Keeping Assist uses radar sensors to monitor several areas around the vehicle. If the radar sensors in the rear bumper are dirty or covered with snow, the system may be impaired or may not function. If an obstacle in the lane in which you are driving has been detected, no lane-correcting brake application occurs.