Pamela, Citizen Contact Centre assigned this issue to Engineering Services

the signals are coordinated with nearby intersections and they run on a fixed time plan, so they may change if one of the detectors at a nearby intersection detected a vehicle that has since stopped or gone elsewhere. In addition, the detectors will automatically trigger a request for a green if the detector is faulty - the request will remain active until the detector is repaired, usually within 12 hrs!.