How can you not know that traffic lights have sensors?

How can anyone who has been driving more than a week not know that most traffic lights have sensors? Hey dumbass, if you stop 20 feet before the stop line the light is never going to be green. You hear all that honking behind you? They are not honking at the light, they are honking at you, you dumb fuck. I can’t count how many times I have been behind that guy. I can’t remember how many times I have been sent to an intersection to investigate a faulty light only to find an idiot parked halfway to the next county looking confused as to why the light never changes. I have to pull up next to them and say that I checked my crystal ball and I can predict that if they pull up to the line the light will change. Presto! How does he do it? It should be grounds for immediate suspension.

Really, most lights? I thought only the ones that specifically had signs saying “Stop Here <-- On Red” had the sensors.

Most times those signs are put up to provide an extra buffer of safety at dangerous intersections, not tell you where the sensors are.

Yeah, most of the lights around here (that I’m aware of) are timed and not sensed. I’m quite often stopped at red lights where there’s no signs of cross traffic for blocks. This is news to me, and I’ve been driving about 16 years now.

It really depends on where you are. If you’re in a downtown area with easily predictable traffic volumes, the lights are probably timed (and coordinated with other signals to keep traffic moving efficiently). If you’re in a more suburban area on a road that sees intermittant traffic, the intersection is probably set up with either a coil under the road or a camera. Even if the intersection is timed during the day, in the evenings when traffic is lighter, it may switch over to sensors.

I was going to say the same thing. In a city like NYC or Chicago where there is basically a traffic signal every block with steady traffic all day, it is more important to have it timed with the rest of the lights on the street. Everywhere else, it’s sensors. Unless you are at a light that hasn’t been improved in at least twenty years(ETA it’s got to be more at least 30 years, I remember the lights having sensors when I was a kid). There are thousands and thousands of them throughout the country. How can someone not be aware of how they work? If I’m at a light and it hasn’t changed for a while my first thought is “I should move up, I probably didn’t trigger the sensor” not “Holy crap I need to call 911!”

Some have sensors here, some are just timed.

Some have both. Certain intersections are timed during the day, but late night/early morning, the major road will stay green until someone approaches the light.

I ride a Bicycle in town and lots of people don’t realize that light frequently have these sensors. Its really annoying. I bet they won’t flip for motorcycles either.

I saw the city turn one of these off once by putting a metal plate over it then paving over that. It was odd, and I still don’t know if it was intentional but it had the effect of timing the light.

Yeah, I’ve seen that too here.

This is especially infuriating at left turn lanes, where there’s either a buried sensor, or a motion sensor at the light itself, aimed at the turn lane. If the mope in the turn lane sits back so as not to let the light know someone’s waiting there, a full cycle goes by without a turn arrow.

But I bet you have learned how to deal with both kinds.

That’s the thing - sensored lights here aren’t indicated in any way (and haven’t been anywhere we’ve driven in three provinces and about nine states), so I assume they all have sensors, and get my car’s ass up to the stop line where it belongs. I guess I am unusual in that I don’t turn my brain off when I turn my ignition on; it sure seems like it some days.

The light at the intersection nearest where I work used to have a pressure switch to activate it. It always used to drive me nuts because the car I was driving at the time wasn’t heavy enough to trigger it. After a while I got used to either waiting until someone else pulled up there or taking an alternate (but very roundabout) route.

You should have filled your pockets with rocks before travelling.

I rember in my motorcylce saftey class the instructor explaining how to handle a situation where your motorcycle wasn’t heavy enough to set off the traffic light sensor. About half the class thought he was joking at first and soon became dumfounded when they discovered traffic light sensors actually exsisted.

It was an '89 Nissan Sentra. I’m pretty sure it couldn’t have handled the extra weight. :slight_smile:

Must have been an old one; most DOT and muncipalities stopped using those a while ago because of problems like that and maintainence issues. Most intersections use either an induction coil that is tripped by a certain mass of metal (and used to drive my brother nuts 'cause his fancy mostly fibergalss motorcycle never tripped 'em), sometimes radar or microwave, or, more recently, cameras that detect the presense of a waiting vehicle. Cameras are becoming popular because they’re a lot easier to get to and fix (no tearing up the pavement) when something goes wrong. Plus it’s easier to program them to recognize things like bicycles.

I may be completely wrong about this, but from all I’ve been able to glean on the web, it seems that all of Chicago’s traffic signals are timed, although 13% of them are able to adjust their timing remotely.

I can’t think of a single intersection in Chicago with pressure sensors. I think I’ve encountered them in the suburbs, but I wouldn’t even have the faintest idea of what they look like.

Lights here (almost all have sensors) have a little bicycle symbol in the middle of the road which tells cyclist where to stand to trigger the light.

There is one annoying light near me where you have to be right on the crosswalk to get it to flip. Besides that, there is no real excuse for anyone stopping many fee from the light, or the car in front of them. I see plenty of people do this in turn lanes, where the unlucky car at the back now blocks traffic.