Comment by BurningFrog

A lot of that will be best solved by making a lot of other actors communicate directly with the car.

Traffic lights will send out the same messages they send to humans by red/green lights to the cars using radio.

Emergency vehicles, roadworks, traffic signs etc will do the same.

Or so I assume, because it makes so much of sense. I know there is vehicle-to-vehicle communication in the works: https://en.wikipedia.org/wiki/Vehicle-to-vehicle