Auckland Transport is responsible for the maintenance of traffic lights.
To report traffic lights not working:
How traffic light sensors work
Underground vehicle detectors
Vehicle detectors are installed under the road surface close to the stop line on the approach to the intersection. The detector loops register the presence of vehicles by the metal of the vehicle bodies.
The detector loops can detect the presence of slow moving vehicles, stopped vehicles, the queue length and register a demand for a green signal, or extend a green signal.
The detectors might not detect vehicles if the sensors were damaged or vehicles stopped too far from the detectors.
Underground bicycle detectors
Some intersections have special areas in front of the traffic queue where cyclists can stop (the area is often coloured green and/or marked with a bicycle stencil). These cycle boxes have underground bicycle detectors that register the presence of cyclists.
'B' bus lights at traffic signals
'B' bus lights at traffic signals give priority to buses, allowing them to drive through an intersection (usually into a bus lane) while other traffic is stopped at a red light.
The underground detectors for bus lights are set up to detect buses only, and don't respond to the presence of cars.