The cars already know those are intersections with lights. I'm not talking about that part. Just the basic logic that you don't go through at speed unless there is a green (or yellow) light.
That's not how any of this works. You can anthropomorphize all you like, but they don't "know" things. They're only able to predictably respond to their training data. A blackout scenario is not in the training data.
Is there anyway to read more about this? I'm skeptical that there aren't any human coded traffic laws in the Waymo software stack, and it just infers everything from "training data".
And the usual setup of an autonomous car is an object recognition system feeding into a rules system. If the object recognition system says an object is there, and that object is there, that's good enough to call "knowing" for the purpose of talking about what the cars should do.
Or to phrase things entirely differently: Finding lights is one of the easy parts. It's basically a solved problem. Cutting your speed when there isn't a green or yellow light is table stakes. These cars earn 2 good boy points for that, and lose 30 for blocking the road.
I don't know if waymos are programmed for that and it could very well be that there were so many pedestrian crossing it wouldn't apply it anyway.