There's an optical sensor (it looks like a camera hanging next to the spotlight) aimed at the area right behind the white line at the intersection. If you're pulled most of the way over the white line like so many people do, the sensor can't see you and therefore thinks there's nobody at your side of the intersection. Therefore... (cont)
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Xylia
Xylia
It doesn't matter how long you wait....and wait.... and wait.... the light isn't going to change until someone else on the other side of the intersection who DOES know how these things work gets it to change for you. That white line is put there for a reason (cont)
Xylia
....and that reason is for long trucks, such as 18 wheeler semis. They need a long turn radius, and the white line is recessed back away from the intersection so that they don't end up blocking the whole intersection because you pulled up too close and they can't fit through the intersection until someone comes and clears the traffic. Just a little PSA.