When I was younger I was always told that ambulances and police were able to change traffic lights if they needed to get through in an emergency using some kind of device in the vehicle - was this ever true?
Emergency services and even buses are given green lights when they need them at the traffic lights. I’m not sure whether it’s a device in the vehicle itself or a link to the system used at the control centre to keep the traffic flowing.
I was in endless discussions with the highways team about a set of traffic lights near to where I used to work which were troublesome to our business and have finally been removed altogether. They talked about the response to emergency vehicles and traffic volumes at the meetings.
When I was younger I was told that flashing your headlights in a certain way on the approach to traffic lights would change them; also at night, slowing down and stopping a certain distance from the lights would change them (fool them in to thinking there was a queue of stationary traffic).
Both urban myths
There is a set of traffic lights on the Great Orme Llandudno that will only change when they detect a vehicle coming down Wyddfyd Rd. If you stop on red and you are not close enough to the lights then they stay on red for you for ever. The traffic, including buses, has priority going up and down the Orme at all other times at that junction.