Signs, sensors or cameras on one stretch of the m27 for more than a day. Atjunction 14 of the m4, there were no sensors or Warning Signs for 11 days. It matters, because if you get trapped in a live lane and the signals dont come on, you will never forget it. It happened to carla heartfield, when she was on the m20 in kent with her baby daughter. I climbed over to get out the passenger side. And i couldnt get my daughter out the car. I think because i was shaking, i was shocked. I remember screaming i was going, were going to die, were going to die. National highways says the radar detects more than 89 of stopped vehicles, but that means one in ten arent spotted. We spoke to someone inside national highways. He works on smart motorways, and he says he no longer trusts the kit. Happens all the time. Sometimes its. Its faulty