What safety feature alerts a driver when the vehicle unintentionally drifts out of its lane?

A lane departure warning alerts a driver when the vehicle unintentionally drifts out of its lane.

The system typically uses a forward-facing camera to recognize painted lane markings. If the vehicle begins crossing a marking without the turn signal activated, it may issue a dashboard warning, chime, steering-wheel vibration, or seat vibration. Unlike corrective systems, basic LDW warns but does not steer the vehicle back.

The technology grew from experimental systems in the late 1980s into commercial truck systems in Europe around 2000. Iteris and Valeo helped bring an early passenger-vehicle version to North America on Nissan’s Infiniti FX in 2004.

A common mix-up is confusing lane departure warning with lane keeping assist. Lane keeping assist can apply steering input, while blind-spot monitoring watches adjacent areas for vehicles. LDW also depends on visible lane markings, so faded lines, snow, sharp curves, or poor weather can limit it.