Although the use of sophisticated technology allows signal light to operate more efficiently, it also introduces the potential for malfunctions to create significant traffic problems. Modern signal systems utilize electronic sensor loops to detect the absence and presence of vehicles. These detector loops are subject to the following modes of failure:
1. The sensors may not detect a vehicle waiting for a green light. This problem can be caused by a number of factors:
a. Vehicles stopping behind or in front of the detector loops. Drivers should pay close attention to the "Stop Lines" (12" - 24" thick white lines) at a signalized intersection making sure they stop and remain stopped just behind the stop lines.
b. The detectors may have malfunctioned due to a variety of reasons. Often, such a problem can be fixed by a technician visiting the signal controller cabinet and "resetting" the detector.
c. Physical makeup of vehicle is not detected by loop. Although this problem has been reduced by advancements in loop technology, occasionally problems still crop up If you repeatedly experience problems with your vehicle being detected, report the problem to the Engineering Department. Some adjustments to the sensitivity of the detectors are possible.
2. The sensors may detect a vehicle waiting for a green light even though one is not present. This can cause considerable problems with mainline traffic during peak volume hours because the signal will give large unnecessary periods of "green" to the minor street cross traffic which really does not exist. This problem is most always the caused by malfunctioning detectors. Often, such a problem can be fixed by a technician visiting the signal controller cabinet and "resetting" the detector.
Contact the Engineering Department at 425-0900 to report problems with the signal lights within the City. For additional information about traffic signals, click here.