Hands up if you would of simply reversed a few feet and moved forward to see if that worked. 🙋‍♂️

The policeman was very good to not just jump the lights and to attempt to sort the issue. Then, by getting community support officers involved and moving his car too. Props to that officer for not being selfish! ❤

I worked for a company supplying road-telemetry and traffic management systems systems (global supplier, also to the UK). There are many different types of sensors but the UK predominantly uses motion detectors on small junctions such as this one because they are very cost-effective and work (mostly) rather well for those types of junctions. Larger or more complex junctions typically have better systems which will trigger on more than just motion and often also combine magnetic loops in the tarmac to detect if a vehicle is standing at the line (which is why you always should drive up to the line, not stop ~5 meters before it!).

I think Ashley was spot on, the traffic just doesn't move after its cycled back to red. The chances of the sensors breaking at that exact moment is extremely slim.

This happened a few months ago with temporary traffic lights for construction work, the lights were situated at a blind bend, I had a copper behind me along with around 20 cars. After 8 minutes on red and no change or other traffic oncoming, I started to creep forward and went straight through with all the cars following, long behold they were manually put onto red purposefully as when we got around the corner there was a construction HGV blocking the road and using its crane to drop off materials. So we all put our tails between our legs and reversed like proper idiots 😂

At least the Highway Code (checks notes) allows you to make a judgement call if you have good reason to believe the lights have stopped working: "If the traffic lights are not working, treat the situation as you would an unmarked junction and proceed with great care." - Rule 176. Given the dashcam evidence, if there was no possibility of trying to reset them by reversing, I'd follow the advice given. Another reason to have a dashcam. It is a good reason for auto-cycling the lights every few minutes, but that's for the engineers to implement. I don't listen to the radio these days, but I used to hear 'stuck on red' quite a lot in the traffic updates on my way to work.

I've been in this exact situation (without the Police though) where the red light just stayed on and would not change. I tried reversing and driving forward but nothing happened. After about 5 minutes I just had to go through the light as it seemed broken. I just treated it like any other junction and gave way to any traffic as you normally would. Luckily it was quite quiet and I just took it really slow and all was well. It's so ingrained in us not to go through a red light (and rightly so) that it really does feel so strange to do it, even under such necessary circumstances.

I'm just dropping a wee message to say thank you. I just passed my test, first time one minor with my dad as my only instructor. Your videos helped me in many situations!!!

Backing away and approaching again would have fixed this. Also on the ground loop system with a motorbike stopping and starting again gives the system a bigger jolt

The lights in Ayrshire are mostly controlled by induction loops buried in the road. A common issue is cars turning right not pulling forward on green light. There is a loop in the road where you wait to turn right, if you're not on top of this then the filter light will never activate. I've sat through 4 or 5 light sequences when the driver in front refuses to pull forward. We could definitely use some general training on how lights work and also reinforce thats its ok to pull forward when right exit is busy, assuming we're not on box junction.

One thing I've noticed with temporary traffic lights in recent years is that if the road is quiet they will turn to red for both directions, then when a car approaches they can instantly turn green for that direction.

As a motorcyclist , I’ve often found traffic lights don’t pick up my motorbike , and have to wait several minutes til they cycle . I recently got stopped for about 5 minutes at temporary traffic lights which kept on letting cars thru periodically from the other direction , they eventually changed to green when a police motorcyclist approached the lights passing the stop here sign .

Was the buried induction loop between the cammer and the Police car? It looked like it, in which case the Police cars poor positioning over the white line meant the system couldn't "see" it, and the car behind hadn't come forward enough to trigger it either.

One big issue I see is people not driving right up to the stop line - they often stop about a car-length back. This is a problem for lights with just one magnetic sensor - it doesn’t detect a car there and so the light stays on red for longer (until the lights cycle themselves). Interestingly, I remember an old Kipkay video years ago which recommended putting a strong magnet under your car - especially for small vehicles like mopeds - to make sure you trigger the lights 😅

This junction has both motion and inductive sensors. You can see the grooves for the latter pass under where the camera car stops the first time (diagonal, third car back) and also, crucially, *between* where the police car stops (halfway across the stop line) and where the camera car stops. This latter set of grooves go straight across the road, and are most easily seen where they interrupt the double-yellow painted lines. I think the lights changed for the first time, not because there was a gap in the traffic, but because it sensed at least three cars waiting (both the first-car and third-car sensors active). Then it was confused, not by a lack of movement per se, but because the remaining cars stopped in positions where the installed sensors couldn't detect them. If the police car had reversed back so that it covered the first-car sensor, this would have prompted the lights to insert this road into the normal cycle sequence; the third-car sensor allows for a priority system, and I think the motion sensor is mostly used to judge when to revert to red.

This happens to me all the time when I'm on my bike. There's this one spot where I always get stuck. If it was just a junction, I'd dismount and wheel my bike through, but it's an alternating one-way system.

While this is an exit from a public car park, there are some places where the exit only works for buses fitted with traffic signal priority (TSP) kit, which is used to detect them and sets the route for them. Also used to give them priority over certain junctions, in which case the sequencing of routes varies, rather than a standard one.

My late father worked in traffic management until he retired some 25+ years ago. There are many variants of traffic light control, with sensors visible above (as here) and buried in the road (as you said), with time of day also a factor, but most have a default "error" mode that they will fall back to if they fail to sense anything for a set period of time. As with everything, that period can vary, with times of 15 minutes not being uncommon in a city. In other words, if it doesn't sense traffic approaching for 15 minutes, the controller will assume there's a fault with the sensors and go to standard timed intervals. Whether it then goes back to sensor-driven is another variable, but you might see a small red light visible on the equipment somewhere which will indicate that it's in this error state.

These lights are 400 yds away from my house, and this happens a lot with them. They don’t recognise me when I’m on my bike. Normally two lanes of traffic line up, depending which lane is required around the bend which I think helps to keep things flowing and ensure there is generally some movement. 🙂

Great vid Ashley. Loved how the police uses his blue lights at the end to deal with the issue.

I agree with the theory that the sensor isn't being triggered. I think it's pointing at the bit of road between the Police car and your viewer. The Police driver got caught out as the lights changed quite quickly, because they're probably timed in favour of the main road. He couldn't clear the junction, leaving him stranded across the line. The other car is too far back to catch the sensor. I'm pretty sure if the Police officer had reversed up to the camera car it would have triggered the lights.

That happened to me over 30 years ago trying to come out of a side street at Paisley Road Toll , Glasgow, to be exact. My traffic lights seemed permantly on red. I waited for about 3 cycles of lights on the main roads . It was early evening , I think , and it WAS quiet, so I emerged against my red light. Of course, there a was a police car from nowhere, and stopped me , but they let me go when I explained. Phew 🙄

Thank you Ashley for trying to get out there the knowledge about road sensors, I honestly wonder what motorist think, when they see the geometric pattern in the road surface at a T/L controlled junction, I'm an ex HGV driver also a Qualified driving instructor from back in the 1980's, I feel sad for the lack of knowledge of young drivers

I have noticed not all traffic lights can detect 2 wheeled vehicles. This can be an issue at quiet times early in the morning. At some lights I sometimes have to wave madly and flash headlamps even though there is absolutely no other traffic coming. Even then sometimes nothing works and I have to "proceed with caution" (usually 6am and deserted). Other times a car or van will approach from behind and rescue me by triggering the lights.

Oddly enough, I had exactly this situation a few months ago, in a major city at night trying to join from a two lane, one way side road to a main road. I waited at the lights for around 6 minutes in the left lane, realised something wasn't right when private hires blew through the lights while the rest of us waited. Once a gap in the traffic developed, I proceeded through the lights treating it as an unmarked junction (As Rule 176 in the Highway Code states). Bad luck for me that an undercover police car had joined the queue around 30s before this and pulled me over once I'd passed the junction. 3 points and a fine with a solicitor advising me not to fight the FPN as technically there is no official guidance on how long a light needs to be out before we can consider it broken, and losing the fight in court could result in a much larger fine and a charge for driving without due care and attention. I tried explaining to the officer that pulled me over that the light clearly was not working and I had several minutes of evidence of this on my dashcam. He wasn't interested and "kindly" let me know that I don't have the authority to determine that a light is broken and that I should wait at the red light for as long as it takes.

I was required to wait at these lights yesterday. Even when we were stationary, the lights changed to green within 2 minutes. I would say they were faulty, they changed red very quickly aswell from my past experience.

Thank you Ash for this, most drivers in my area do not or not aware that most traffic lights nowadays have sensors on them. In a shopping complex where I work, we have to tell drivers who are stuck at a traffic light is that they need to drive up towards the white lines as the sensors cannot detect any vehicle

Hi, software engineer 👋🏼 I don’t pretend to have worked on traffic light systems but I spend a good chunk of my time observing technologies in our every day (and maybe getting a bit frustrated with the build of some traffic light systems in particular)! TL;DR don’t flash your lights at traffic lights. It does nothing and so you look silly. Sensors you see on top of traffic lights are used to detect MOVING traffic as the video points out. However, the under road sensors (induction loops) detect traffic that has moved over it or is stationary above it. The best traffic lights have under road sensors 200m or so back, which means the traffic lights are green by the time you reach them. The worst traffic lights keep the major road waiting on a red light, and the empty-of-traffic minor road on green. The sensors on top of traffic lights are generally infrared or microwave. For simplicity, let’s just call it radar. Radar can detect stationary or moving objects, but how would it know if it is detecting a stationary car or a rogue pigeon eating someone’s McDonald’s fries? Instead the radar sensors measure speed to solve this, with a prefixed speed to determine a car. A pigeon is unlikely to be consistently moving towards the traffic light above 5mph (birds fly erratically, for example). Induction loops measure, you guessed it, induction, thanks to the metallic build of cars. This can be used as a switch. It doesn’t require constant induction to know that a car is there, if the induction changed over the threshold and then disappeared, this would be a sign that a car has passed over it. Here’s the general basis of the algorithm I’ve observed with some made-up numbers, and some brief research would seem to confirm (please bear in mind every traffic light system is different, but in a general sense the following is likely to apply). A basic set of traffic lights should have a fixed timer for an interchange. For example RED_TIME = 120 //Seconds GREEN_TIME = 30 //Seconds WHILE (TRUE): //Repeat indefinitely WAIT(RED_TIME) CHANGE("GREEN") WAIT(GREEN_TIME) CHANGE("RED") A good traffic light system should build on this by adding vehicle actuation (sensors). A separate process will run: SENSOR.ON("Vehicle Detected", REDUCE_RED_TIME(RED_TIME * 0.1) // Fast forward the red time by 10% of the remaining time to reduce waiting time ) This means that when a sensor detects a vehicle (or vehicles depending on build), that traffic will get prioritised, but in the case the sensor hasn’t detected anything, there will still be an opportunity every 120 seconds for vehicles to pass through which is a failsafe. Most traffic lights will do this. On complex junctions though, there are obviously other considerations such as traffic directions and sequencing.

One thing this shows is that traffic lights need two sensors: cameras and ground loop, in case one of them fails.

There's a set with just movement sensors near me where queueing traffic blocks the side road so they go green but there's no movement so they immediately go red again. Needs an induction loop as well to detect the waiting vehicle.

Yep this happened to me. I was cycling to work and there was a massive queue to a traffic light with sensors. Then cars coming the other direction came through (the traffic light was there as the lane was too narrow for cars in both directions). The last car that came through stopped and pulled in to park right in front of the traffic light, meaning no cars were able to move, so the traffic light stayed red. I finally decided to cycle up to the traffic light and wave at the sensor. Low and behold the traffic light changed to green! They definitely need to detect movement.

Difficult without police being there but I've always assumed that after waiting around 4 minutes the lights must be stuck and to proceed with caution always remembering that in the event of an accident/collision you would be at fault for crossing a red light. However, I would be concerned though if there was a possibility of there being a red-light camera in operation.

I think if i had no police assistance and it was safe for me to do so after that long waiting I'd of carefully gone through the red light and hopefully the sensor (if it wasn't broken) was triggered by traffic behind me to get things working again. I do know at work as a bus driver if I had a situation like this, I can report to our control that a set of traffic lights appear to be stuck on red, on said road, and they can report it to the local council.

Glad I found this again, Happened outside Asda in Stafford. Someone blocked the exit route on the Box Junction and the lights cycled twice and then got stuck as nothing was moving and the sensors must have decided there was no need to change. The roads in Stafford were chock-o-block again due to an accident on the M6. Decided that when said car had moved out the way to pull forward slowly on Red and when it was safe to proceed off, the car behind followed too. Hopefully that got the lights going again. Box Junctions are there for a reason, no real excuse getting caught on one unless there's exceptional circumstances.

Had the same thing happen at a similar junction last month. The main road lights would go red for pedestrians several times, but our side road light was stuck on red. No one in front had the sense to move their car back and forth to activate the sensors. After a 10-minute standoff, the guy in front had enough and started to make a U-turn and just like that, our light turned green. Next time, I might as well bring a tent and camp out if no one moves.

you'll sometimes get the ground detection loops on smart junctions with cycle lanes - obviously since bikes are smaller (and sometimes not made up of enough metal) they'll never detect you. in these cases i normally cross the junction with care in the pedestrian phase after pushing the button you can also treat a broken sensor traffic light as a stop sign if and only if its cycled through the same phase twice and ignored you, just be very careful

There's a set near me that defaults to red on main road, green on side. Even though you didn't explicitly get me started on it, traffic light irritations always bring my mind to those which are incapable of detecting cyclists.

I had a similar situation where the traffic light was not changing on my driving test. Observed multiple full cycles where it did change to let traffic out from the opposite road but not mine on a cross roads. I made the decision it had failed told the examiner and said I was going to procede with caution provided there was no traffic. The examiner didn't say much at the time but afterwards said he agreed with my assessment. I passed the test

Thanks for highlighting the issue. Too many people here in Edinburgh stop before the magnetic coil sensor, or after it in the bicycle area. I often get out and ask them to move over the sensor. I sent Edinburgh Council a very detailed description of the problem at my local junction. No reply or action taken. Considering putting my own sign up saying "Stop here to trigger the green light"

When on a relatively free flowing road with multiple traffic lights, I like to have a few vehicles ahead of me in the hope they will trip the sensor for me. I've managed to get quite a long uninterrupted "green wave" using this technique, having the other vehicles do all the work of slowing and then accelerating to the next set of lights. In the meantime, I've been able to maintain a relatively constant speed.

“Smart lights” as they're sometimes called here in NL. Though no mounted sensors, usually just loops in the ground that detect cars and even cyclists approaching or waiting. Do think people shouldn't take these for granted though, I've had seen plenty red light jumpers going for it, because they expected green and didn't bother to slow down. Just because these systems aides traffic flow, we shouldn't give up on paying attention.

I was caught in a similar situation last year. I was coming up a very major road in Blackpool when the traffic lights didn't work. And despite cars and buses queueing up behind me, I sat at the red lights for 3 revolutions (4 way junction). On the 4 revolution though I carefully jumped the red lights and all the following traffic did the same. They were fixed later on that day though.

I’ve seen similar situations like this with power outages when the lights are out completely. What I find is risky but the only course of action is to treat it like a junction with no lights and wait for a gap, sometimes assisted with a flash of the headlights of or a sound of the horn to warn other traffic if its a closed junction

Hi Ashley, I just wanted to say big thank you for all your videos all the way here from Serbia! This past Monday, I passed my drivers test on 2nd attempt with 5 minors! Your videos have helped me learn a lot about traffic flow and how to deal with certain situations. I will keep watching but now I don't have to stress about passing the test 😂

The sensors are built into the roads in Australia. Some drivers stop so far forward that I worry they won't trigger the sensor so I drive right up behind them so my car covers the sensor. I can remember years ago being stuck behind a truck waiting to turn out of a shopping centre. He was the first in line but too far back to trigger the sensor. I had to get out of my car and tell him to drive forward or the lights would never have turned.

This has happened to me many times. I used to work as a private hire driver and working nights the lights used to hang on red. I blamed how some roads come out towards the lights, especially a side road so close to the lights and when you come out, it never picked you up. The only best way I found was to reverse back up and drive up to the lights. Another thing I found was if you were over the white line or far from it, the lights won’t change because it will not pick you up.

This happens to me at one particular junction in Camberley almost monthly. Typically there are cars ahead of me, which I presume haven't been able to move through the junction because of traffic. I've had to run that red light about 4/5 times now. The difference is, though, that the light is 3-way and it's only my side street that gets stuck on red. Usually I have a few seconds to make the turn safely between the lights stopping one lane of traffic and going green for the other.

Pet hate - sensors that don't detect me on my bike!

There is actually a magnetic sensor on these lights, you can just about see the wire buried below the white arrow. There just wasn't enough of the police car over it.

One nice option in North America if traffic lights ever get stuck on red: The fact that it's legal to turn right on a red light over there, with a few caveats to be obeyed. You can also turn left on a red light over there, providing the street you are turning into is one way. Again, a few caveats exist but it's a useful option to have in case of lights stuck on red...or indeed to get out of the way of an emergency vehicle. Oh and over there, red light cameras can distinguish a legal turn on red, as long as you come to a complete stop behind the line first. They even have signs at such intersections to remind you to come to a full stop first.

Same happens down my way outside an international ferry port, when the ferry kick out and the traffic flows everything works great, but if you are only a couple of motor bikes who pull up side by side occasionally this happens, even though you are sitting on top of the road sensors buried under the tarmac for some reason it doesn’t know that you are there, Trying to back up a Harley Davison without a reverse gear is a no go, so you sit for a while they go through the red light when the junction is clear. [luckily its wide open and you can see everything around]

These traffic lights detect cops and hold them up

I had a similar experience in the middle of Stratford upon Avon a few weeks ago. I was a few cars back in a traffic queue on a minor road approaching a traffic light controlled crossroads. I could see the lights and they didn’t change from red for over 15 minutes. It’s a horrendous junction in rush hour as traffic on the other side of the crossroads backs up too so there’s often nowhere to go even if the lights are green. I wondered whether they’d stayed on red for that reason. I eventually phoned (hands free!) the police but the lights did eventually change before anyone came out.

Hi there, I work as a traffic signal engineer. You’re correct in fact that the ‘sensor’ is looking for moving cars which is why it’s stuck on red. It’s called an MVD - Moving vehicle detector. Usually smaller side roads also have a stop line detector whether that’s a physical in road induction ‘loop’ or an above ground sensor/camera. This would detect a car that is waiting at the stop line even if it’s stationary. It looks as if there isn’t one here because usually they have a failsafe and get stuck on rather than off. If you report to your local council they are usually pretty good when it comes to traffic light issues and they might have one installed. Cheers 👍

I seem to remember being told somewhere, might have been during my PSV training that if lights don't change after 5 minutes carefully move through them.

I've had one near me on the school run every morning, where the light turns green but ambulances frequent in the junction ahead with their blues on, for this reason cars have to remain at the green light. The light then turns red again quite quickly, and the same cars remain at the light. Usually, I ended up waiting there for a little while to confirm they are not working, the first few cars can go through when it's safe and then the sensor will detect the built up traffick moving forward. Not much can be done about that one, though; it does happen frequently.

I once came across the opposite problem. The lights were going green in both directions, I almost got knocked off my bike. A friend and I decided to play traffic cop and directed traffic and tried to explain to drivers what the problem was. Eventually some police officers came along and took over. They just told us to bugger off, no other discussion. I guess a good deed is its own reward.

You may also find a relatively long wait at some junctions with a right turn controlled by lights. There can be up to 3 induction loops for queue detection and your filter light will not turn green until the furthest loop from the stop line detects a vehicle. If it's a right turn from a particularly busy road this timing may be extended so that a certain amount of extra time will pass before you get the green depending on how much traffic is on the main.

In the Netherlands for big junctions, there are often 3 magnetic loops per side. One for warning the system a car is coming, one queue loop that lets the system know how big the queue is, and one loop at the stop line. Magnetic loops can be problematic for motor drivers because they can park in between the lines.

I live close by to where this footage is from (Midsomer Norton - Bath and North East Somerset) and these lights have been a nightmare for years. The cycle takes a very long time and exactly as you said the sensors don't pick you up. Was stuck here on my motorbike once for a while until another car approach behind me tripping the sensors...

Another function of sensor would appear to be speed control. I commute (at night) through a set on a main road which as you state in the video, remain at green until traffic from the junction triggers them. Although, if you approach these lights (on the main route) even 5-10 mph faster than the speed limit, will trigger the lights to go to red regardless of the fact there is No other traffic anywhere.

There's a hilarious set of traffic lights I used to know by a wide corner near a train station. If you cut the corner, you missed the road sensor and the lights stayed on red for ages. If you took the corner properly and stayed in lane, you'd trigger the sensor and the lights would be green when you got to them (assuming nothing coming the other way). I once had to wait there for a pick up for 10 minutes and only saw one car do it right :)

I had an issue with a particular set of traffic lights on a single-lane hump bridge near where I used to live in Reading. My small 125cc motorcycle would never trigger the electromagnetic sensor in the tarmac. I usually had to wait for a car to come along and trigger the lights for me, but as I went very early morning most days this could sometimes take a while...

Motorcyclist in NL here. My longest wait was 7 minutes at a light in an eerily empty intersection, ended up running the red. It is quite a common situation, on a bike you need to approach the intersections in the central position of the lane, otherwise the sensor is likely to miss you.

I have encountered a similar issue whilst commuting by bicycle late at night, when stopped at traffic lights with the (magnetic) induction sensors embedded in the road (you can usually see the lines in the road where the sensors have been set into the asphalt). I discovered that to "tell" the traffic light controller that I was there, I could lie my steel bicycle frame down onto the ground, which would immediately trigger the light-change sequence so that I could proceed with my journey

Yep. These EXACT lights always have this issue. That's out of the Sainsburys car park in Midsomer Norton. I live just down the road from these and visit the store regularly. These lights are an absolute nightmare. It's a very busy place around midday, so there is a high volume of traffic. Driven out of this junction many times and I'm usually stuck for around 5 to 10 mins every time. It is getting a bit ludicrous now...

We have a sensor light like this near me and someone must of got so sick of it happening they have stuck a handmade sign on (laminated) too saying move to the line or the lights wont work. Love the sign lol makes me smile everytime 😂

My son had a similar issue when he had a small motor bike. The sensors in the road did not trigger as the mass of metal in his bike did not register , he would often have to wait for a car.

I've noticed that in my area, traffic lights on main roads will default to red, while emerging traffic from side roads has green lights. I think this has a similar effect to speed bumps to stop cars absolutely sending it when the roads are empty.

Been in this circumstance before and after waiting so long called 101 to let the cops know so they could relay the issue and then I edged out and used it like a normal T junction. Always a gap at some stage 😊

Hello Neal, you are right the sensor relies on movement passing over the magnetic triggers in the road, motorcycles have this problem when they don,t activate the trigger and holds traffic up behind, provide camera evidence from camera activity and the police/DVLA or the CPS won't action the event.

Over the 40 years I've been riding motorcycles I've been stuck at red lights plenty of times due to the underground sensor failing to register my bike. I usually move the bike around trying to trigger the sensor. Failing this I go through on red taking due care. I have actually been caught 4 times by the police going through on red. Fortunately each time I respectfully explained the situation and they recognised I'd taken good care going through. I should mention that each time it's been late at night with little danger .

The two principal sensors used on traffic signals are microwave detectors (usually a small box on top of the signal) and inductive loops (wire embedded in the road surface). The microwave detector has a microwave transmitter and the reflected transmission is picked up by the detector. A moving object will create a Doppler shift with the reflected signal. If the detector observes a change in the reflected signal it assumes a vehicle is approaching. Microwave detectors usually have a minimum trigger speed for approaching vehicles to stop false positives. Inductive loops generate an electromagnetic field, a metal object within the field changes the properties of the field which is detected by the field circuitry. A few observations: When a signal is controlled by an induction loop at the traffic light there is sometimes an earlier loop to detect queue length. If a vehicle is waiting at the lights on the induction loop if you stop your car on the earlier loop you can trick the system into thinking the queue is longer than it actually is therefore reducing the time of your red phase. Puffin crossings (pedestrian user-friendly intelligent) have a microwave detector to sense if people are still on the crossing. Impatient drivers who keep creeping forward can sometimes be detected by the crossing occasionally confusing the system into thinking a pedestrian is still crossing therefore making the driver wait for longer. The microwave detectors on temporary signals often have a small led which illuminates when the sensor detects movement, you can watch for that led to make sure the lights have detected you.

I've just came across this video and recognised that this is in my local town of Midsomer Norton.These traffic lights and the lights around the corner have always been a problem. On a busy day you have 2 lanes of traffic coming from the left which then have to stop just 10/15 yards past these lights at another set of lights. You only need someone to end up stopping in the box junction in front of these lights to mess everything up as nobody can then pull out when these change to green. By the time the other lights have changed , these will have gone back to red.

had this issue with a single lane bridge near me, some roadworks caused havoc as people kept blocking the oncoming lane behind me and people kept coming under the bridge, so our light stayed red as people were stopped under the bridge. waited 2 minutes before figuring out that the lights weren't gonna change so some of us had the run the red so the road could be cleared

I recall an article from the late 90’s saying the traffic light phases in London were modified to make flows less efficient. To purposely slow to flow of traffic. Also induction loops in the roads can be used to calculate traffic speed! If you drive above the speed limit on the approach to some lights they’d turn to red.

You get this quite a lot when riding round on a bike as the sensors don't pick you up, asked a South Wales police officer about this when he saw me stuck at a junction and he said if it happens again at any junction to give it a minute and if it doesn't change when it's clear to emerge carefully with clear observations as if the lights were marked as out of action.

This was interesting. Never had this happen to me, but now I know what to do should something like this happen.

It is obstacles I go through as a delivery rider using a motorcycle, especially at night! So I always try to communicate the sensor by reversing or coming near the sensor, and most of times it works

I’ve been in this situation before, it usually ends up either the person at the lights skipping the red light carefully, or if there’s space behind them, they reverse so the sensor picks them up.

This is a common problem in Edinburgh. Too often I will come to a side junction, the two or three vehicles in front will have time to go through before the amber light comes on and because I or the car in front are only creeping up to the lights, I have sat there as the lights go through two or three cycles for the other roads before the one we are waiting at change. It might help the 'main' volume of traffic, but I see so many other vehicles that are wise to this problem and will risk going through on the amber.

I had a similar issue with temporary lights and there was que with drivers becoming impatient, in the end very cautiously i had to go through the red light because it seemed to be not working. Just had to make the call on the spot

The trans penn cycling trail crosses a busy road near Sale. There is a sensor there which only works for the cycle if I really push down on the front wheel as it goes over it. Otherwise I will wait endlessly until a car comes.

Motorcycle rider - This happens to me all the time with these sensors. Luckily I'm in London so a car is not far behind usually, I normally just pull forward into the cycle box or beyond the white line a little and tell the car behind me to come forward. Lights always change within 10 seconds of this.

I got stuck in Sheffield at a complex junction near the Meadowhall centre. It was 4am and I realised I was in the wrong lane and did a last minute lane change. I must have missed the sensor in my lane as the lights went through several cycles ahead of me but never changed off red for me. I even tried reversing up and the light still wouldn't change. In the end I just had to jump the red light. There were no other vehicles on the road anyway.

The lights on the a518 near stafford used to be terrible for this, not sure what they changed with them but now if i flash my bikes lights at them you can see the little red indicator light on the sensor register that im waiting. granted this is at night time though, so they may default to a different system during the day. often joked it was picking on my little 125, making me wait 15 mins in the pouring rain lol

I work in traffic management ( temporary traffic management) includes temporary lights, road closures etc. Usually the sensors are motion sensors especially on temp lights, but I have seen more recently lights set to timings which makes a much longer wait time on RED, if you are driving towards a set of temporary lights the (When red light shows wait here) board is supposed to be 15 metres back if you go by the traffic management Red book, but you soon realise at that distance the lights sometimes struggle to trigger so need to just slowly move forwards and the red light will trigger on the sensor just above the red light.

There’s a similar set of traffic lights in Stoke-on-Trent (Whieldon Road, under the A500) that has similar glitches. If the magnetic sensors don’t register movement then they stay in red, to allow the busy slip road traffic to keep moving. It’s a tricky hill start, and when I taught manual lessons, I’ve had to get my pupils to reverse back if they stalled at the lights to get them to cycle again. It also causes problems during busy times when the slip road queues up, the lights don’t cycle properly and it’s easy to get marooned behind the red lights. Good teaching points though, I sill explain the potential problems to my pupils even though I teach automatic now, as they may experience the same issues in the future.

You are correct Neil. If both car had reversed up and re approached the sensor picks up the movement. It depends on what is behind our viewers car if was able to reverse. Just like any other PIR sensor. It's sensitivity is quite low so people don't set it off but sufficient to see a bicycle. Approaching this sort of sensor is best if you approach at nice even steady movement it will pick up and cycle the lights. On a cold day the sensor is more sensitive than in hot sunshine as it can see the difference in the infrared signal. Also if the engine of the vehicle is hot it picks it up quicker. Coming out if the car park the vehicle engine could be cold so less infrared signal.

I have experienced several situations where the sensors in the road have not detected my motorcycle and as a result have failed to cycle. Also several occasions when on busy intersections cars have stopped too far back from the lights and failed to trigger the sensor causing considerable queues.

I used to pass through a set of traffic lights in Camberley town centre that had this same problem. Basically, the police car moved into a dead spot and fooled the light's sensors into thinking there was no safe changing option. That particular one was a right turning lane that only worked when the junction was clear and there was traffic waiting. The best thing the police car could have done was (apart from stopping behind the line in the first place) to continue the manoeuvre when it was clear and let the next car stop behind the line.

I used live on a rural side-street that was served by a south-facing set of traffic lights with a movement sensor attached to the top. At certain times of the year, on bright and cloudless days, when the direct sunlight was at the right/wrong angle, the movement sensors seemed to get dazzled and sometimes would not register oncoming traffic and therefore not signal the main road to stop. If we could, we'd reverse and approach again. But this sometimes wouldn't work, so in the absence of any pedestrians, and as the main road was infrequently used anyway, we'd have to peek-and-creep our way slowly past the light frozen on red.

This sort of thing happened to me then I thought of one of your videos and moved my car slightly forward. On the next change of lights mine went green. ✅

I preface this with I live in the states..... Here I would say almost all have the sensors in the ground, or under the tarmac as you called it... And if you know where that area is, then drive onto it. I have a signal near me that is a left turn off the freeway exit, but the right hand turn is not with it at the same set of lights, it's also on a steep incline and it's a strange kind of left hook if you will. Well it also doesn't like to change if you aren't on the plate under the tarmac, a very specific way. You also can't flash your highbeams at the signal because of the angle they sit at, because a lot of lights here have a sensor on the top of the light as well. So what I learned a long time ago was to reverse back and roll forward again. And to do this as many times as you need, or if traffic allows. Motorcycles here are notorious for not being heavy enough to set the sensor off. And will at times get stuck at the lights till a heavier vehicle pulls up. So with the light near me that does this, I just roll back and forward again, but I've also learned to stop on the sensor in a little bit of a different way, and it seems to work... I also think in some places here that if you've sat at a light for over 3 minutes (don't know what the exact time would be), and if there is no traffic you are allowed to treat it as a 4 way stop, 2 way stop, etc....

Had same thing happen in my town. After waiting over 5 mins I was about to ask all the traffic to back up so that the cars at the front could move. Is was about 5 cars back so not close enough to tigger the lights myself. In the end the car a the front edged over the red light and into the stationary traffic on the main road. This movement immediately caused the lights to cycle. Lesson is leave some room to to car in front so you can edge forward

Traffic light sensors are a frustration as a cyclist, too. Many times I have waited at a red traffic light, for the lights to only change upon a car or other larger vehicle pulling up behind me.

Near where I live there's a set of traffic lights that ALWAYS get stuck on red for ages. Traffic will be stopped in all three directions and yet the lights stay red for a good 25-30 seconds, the pedestrian crosswalks aren't active either as the red man is shown. I once got stuck at these in a marked police vehicle with a member of the public in front of me. I pulled up next to them and told them to follow me through slowly. Blues on, slowly went through checking to the left and straight ahead for oncoming traffic. We had sat there for literally 2 minutes on a red light, no car queuing opposite on the other side of the road coming towards us at the same lights and nothing to the left either. It was around 1AM and myself and the other car were the only vehicles on the road at those set of lights, no pedestrians around either. Sometimes they really do just break or get glitched out.

I remember my driving instructor telling me about a somewhat similar situation that happened to him with another pupil. They'd pulled up at the lights whilst they were on red, lights changed and when they tried to move off they stalled and the lights changed back to red. The other sides of the junction then went, then went again and I think it was after quite a few minutes without the lights going green on their side of the junction. I think it was around then the instructor decided that given the queue behind they would just need to go through the red. The instructor waited for an appropriate gap in the traffic and went through the red doing a left turn to avoid crossing other traffic as much as possible.

Back when I was riding on small motorbikes (50/125) I had a couple of instances like this. no one else was around in any direction, after 5-10 minutes I would shut my engine off, walk the bike round the junction and away from the traffic lights, then get back on and carry on -I’ve found bigger motorbikes don’t have this trouble as often. if there’s a car behind me I’ll roll forward a little and encourage them forward to where I suspect the magnetic sensor is, it’s the same reason that I usually filter to be the second vehicle in the queue

Have lights near us that you need to have the front of the car on or slightly beyond the white line to get picked up otherwise traffic going right gets skipped in the light cycle. Many cars, especially learner drivers it must be said, stop a good 5-6ft before the line and end up sitting for a prolonged period through multiple cycles before they get impatient and start creeping forward at which point they'll hit the line and the lights will pick the traffic up. This can cause quite a lot of traffic to build up and someone put up a cardboard sign on the traffic island telling people to make sure there car was forward of the line to stop this happening.