It'll be awhile yet before self-driving cars proliferate on the world's roads, but every new model brings more automation to bolster the human driver's limited attentional and responsive capacities, and to relieve the human driver of the tasks they don't absolutely need to do. How do we reasonably divide up the tasks between driver and car, though? Some tasks are obvious: we don't expect the vehicle's occupants to inflate their own airbags just before a crash, or to remember to activate the brake lights when slowing or stopping the car, or to manually flash the turn signals on and off. In other cases, things get murkier.
For many years, all of the vehicle's visibility systems were controlled directly or indirectly by the driver, who switched the headlamps on and off (and the instrument panel, licence plate, front and rear position, and sidemarker lights along with them), selected high or low beam, and activated the windshield wipers and washers as necessary. Those kinds of tasks have been automated over the years, to varying degree—and that variance has grown large enough to make problems. Some cars do and some cars don't automatically switch on the headlamps or change from DRLs to full lamps with the rear and side conspicuity lights when it gets dark out. That used to be a self-solving problem; drivers in cars without automatic lights would sooner or later find themselves driving in the dark: no instrument lights, no pool of light on the road ahead, and sometimes opposing or following drivers would flash their lights. All of that was usually enough to jog the driver's attention and they'd hit the light switch and drive on, properly lit. If not, they were probably drunk or otherwise impaired, and sooner or later a police car would flash the other kind of lights and get the sloppy driver off the road.