Blind spot detection systems use sensors that monitor nearby lanes and determine when other vehicles approach or enter a vehicle’s blind spot. When this occurs, the system warns the driver with a visual alert which usually appears either in or near the sideview mirror. If the driver signals a turn or lane change the alert changes. It may become brighter or flash or an audible warning may sound. Some systems also may activate break or steering controls to keep the vehicle in its lane. The alert stops when the adjacent vehicle is no longer in the blind spot.