2013 Toyota Land Cruiser Owners Manual - Page 275

2-4. Using other driving systems Radar sensor (Radar type only) Detects vehicles or other obstacles on or near the road ahead and determines whether a collision is imminent based on the position, speed, and heading of the obstacles. 2 When driving When traveling on a road with very light traffic and very little to reflect the radar waves emitted by the radar sensor, the system may decide that the radar sensor is dirty, even if the sensor is not actually dirty. The system will automatically restore itself when reflected radar waves are detected. 283 L/C200_U (OM60G36U)