Traffic Signal Stop - Turn Light Tripping Sensor

[Randy B]

It's all about timing when pulling up to the light. I can tell you that it does not work. I lived in Chicago for most of my life and it NEVER worked. I had friends try it and I even did, but it never tripped the light. If you managed to trip the light the indicator light on the top would flash in your direction showing that yours was the direction opened for emergency traffic and a solid light would come on for the cross traffic. Watch for this when you think you are tripping the light, because I can guarantee you that it won't be lit up (unless an emergency vehicle happens to be approaching).
They design and test these systems so that they can not be falsely activated by non emergency vehicles which is why the people that have been busted tripping them have had devices in their vehicles in order to do so. If it was possible to trip them by flashing your lights at it, don't you think that there would be gridlock from everyone trying it? Think about it.