Lane departure warning
The prerequisites for a lane departure warning are an identified lane and a specific driving speed. These make the system fundamentally ready to give a warning. When crossing over a lane is imminent, the system warns the driver through a vibrating steering wheel. The system firstly uses one or two identified lanes to calculate the vehicle position relative to these lanes. Using the yaw rate and the driving speed, the remaining time for driving over a lane is calculated. A warning is output in good time before crossing over the marking.
A warning is only output once when approaching a road marking. The warning lasts for a maximum of 2.5 seconds. No further warning is output if the vehicle remains on the lane marking. A replaced warning is only possible after steering back into the lane or a lane change. A lane change intended by the driver: no warning is output when the turn indicator is operated as an input signal.
The warning is ended in the following conditions:
- Driver steers back into the lane
- Lane change is carried out
- Vehicle is on the line for longer than 2.5 seconds
- Turn indicator for lane change is operated
- Brake is operated firmly (depending on brake pressure).
The speed for activation of a warning is country-dependent.
- Europe: 70 km/h
- United States: 40 mph
- Japan: 50 km/h
The displays for system and warning readiness are shown on the instrument cluster as well as (vehicle-dependent) in the Head-Up Display.