I assume you mean the perpendicular direction crossing lights?
Most pedestrian lights have delays longer than that in California for safety so you might stop at a green light.
Also, if nobody presses a button ped-lights don't even turn on, just like left turn signals don't turn on without a vehicle triggering it.
> Also, if nobody presses a button ped-lights don't even turn on
This is no longer true in many cities. Most SF crosswalks don’t require a press anymore, many don’t in LA, and all don’t in New York. AFAIK it was a Covid thing, back when people thought surfaces spread the virus, but it stuck.
often, in the form of the pedestrian signal.
> try to clear it before it turns red?
This is the rule in much of the world, yes.