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What is a Lane Departure Warning System?

Lane Departure Warning System

A lane departure warning system, which is also known as a driver alert system, is an advanced driver-assistance system (ADAS) feature that alerts drivers if they are unintentionally drifting out of their lane.

The primary function of a lane departure warning system is to detect when the vehicle is about to cross over a solid white line or edge line between two lanes and alert the driver. Some drivers find this type of alert helpful. A lane departure warning system can also be used on multilane highways with solid white lines dividing the lanes.


  • The system uses a brief, gentle steering wheel turn to alert you when you may be unintentionally drifting out of detected lane lines, so you can steer to stay safely in your lane
  • If needed, you may receive additional Lane Departure Warning alerts
  • System alerts do not occur if you’re using your turn signal or it detects you may be intentionally steering


If your attention wanders and your vehicle starts to drift out of the lane, a lane departure system warns you with a beep, vibration, or visual cue on the instrument panel.

If the vehicle also is equipped with lane-keeping assist, it will go beyond just a warning: It will make a minor steering or braking correction to keep the car in its lane. Common names for these systems are LaneSense (Chrysler), Active Lane Keeping Assist (Mercedes-Benz), and Lane Departure Alert with Steering Assist (Toyota). NHTSA recommends lane departure warnings.

While the Lane Departure Warning System is still pretty new to a lot of people, it’s been around for a few decades. You’ll find this feature on newer cars. If your vehicle is equipped with an advanced driver-assistance system and you had to have your windshield replaced, you need to have your camera recalibrated. Contact Bee-Line Calibrations and we’ll come to your home or office and recalibrate your windshield camera for you.