[ElectricSpoon]

A less known feature of some crosswalk buttons is that some have accessibility features. I've seen a few that were pointless when pressed due to automatic triggering. Long-press and you'll get longer time and an audible indicator while crossing.

[merlyn]

In downtown Minneapolis, the whole of downtown is on computer controlled traffic light grid, so the crosswalk buttons don't change any of the timing of the traffic light grid.

But on all the ADA upgraded intersections, the crosswalk buttons DO start announcing the count down time, and what intersection they are at.

So, they do something, but they won't change the time it takes the light to actually change.