Why do left turn arrows only seem to work at certain times?
Left turn arrows only come on when the controller equipment at the intersection recognizes that a vehicle is present. If a vehicle arrives too late to be detected, the intersection may skip the arrow. Some left turn arrows use third car detection. This means that the left turn arrows operate when three or more vehicles are present in the left turn lane. Sometimes the detection equipment does not pick up a vehicle, or will place a constant call into the controller; if you would like to report a left turn signal that does not seem to be functioning properly, please call Signal Systems at 480-644-2160.
