When changing lanes, the Blind Spot Assist function of DISTRONIC PLUS issues visual and audible warnings if it senses a possible collision with another motor vehicle. Using the Parking Guidance system’s close-range radar sensors, Blind Spot Assist monitors the areas directly alongside and behind the car, thus covering the zones drivers cannot see using the exterior mirrors – the vehicle ‘blind spot’. If it detects another vehicle (including motorcycles), the system flashes a red warning light in the glass of the exterior mirror to inform the driver. Should the driver fail to notice the warning and initiate the turn signal, the red warning light in the exterior mirror will flash while an audible alarm is issued.