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[–] 24 points 2 months ago (2 children)

I’ve seen all kinds.

Some will instantly change the lights and give cars a red.

Some will trigger the lights after a period of time - maybe synced to another traffic light, or a timer so it doesn’t change too quickly/often.

Some won’t actually cause the lights to change any sooner, but pressing the button will cause the chirping sound to play for people with visual impairments when the light finally changes.

And sometimes they’re broken and trigger the lights even when nobody pushed it. Those are fun when you’re driving a car.

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  • [–] 11 points 2 months ago

    Their behaviour is programmed based on the characteristics of the intersection. If it's a very lopsided one where one direction has heavy traffic and the other very little, then the button might trigger a light change.

    Other times, the light timing doesn't change, but the button will trigger the crosswalk to indicate walk after the next change.

    Other behaviours I've seen is it changing the advance green/left turn signal, or showing the walk symbol while all traffic is stopped.

    And then I've seen a few that do appear to do absolutely nothing - but that doesn't mean that's the case. For example, an intersection might have a button that only does something at night when there's very little traffic, but doesn't during the day when the intersection is constantly busy.

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