A hardware failure in the system that co-ordinates the communication between traffic lights was causing havoc for some drivers last night and this morning.
As a result of the fault, each junction at Queensferry Road and a number of other junctions, such as Clermiston Road North, were running in ‘isolated’ mode, reducing the efficiency of traffic flow between junctions.
Isolated mode changes the lights based on vehicle loop detectors and pedestrian push buttons and is usually used in areas with low volumes of traffic.
While the roadworks did contribute to the delays, the issue with the lights also caused chaos for many.
External technicians are attending the issue “as a matter of urgency” this morning but drivers have been wanred to expect some delays and unusual timings of lights as tests continue to run.