Lane departure warning

WARNING: This page is about a different car, the 2013 BMW X5, 2012 BMW X5, and 2011 BMW X5. However, it is still accessible from the selected car via links, so may be relevant.

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. The time remaining to cross over a lane is calculated with the aid of the steering angle and the driving speed. 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 renewed 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 minimum speed for 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 the Head-Up Display.