How To Trigger A Green Traffic Light

 Image via Vit Brunner on Flickr, edited by the author.
Image via Vit Brunner on Flickr, edited by the author.

Having to sit at a red light is a miserable experience. There you are, trapped with your thoughts, staring at an inanimate light you let dictate your daily life. How sad is that? What are some other sad thoughts? How can I make this light turn green and escape this introspective hell? Is that guy picking his nose? He totally is.

Well, unless you are Seth Green in the remake of The Italian Job, starring Mark Wahlberg and Charlize Theron, you likely can not just whimsically hacker-man your way into getting the light to turn green.

But, depending on how the intersection is designed, it may be worth it to check out this video from SciShow, which explains the different types of ways green lights are timed and programmed to get you on your way.

In the video, Hank Green explains the various types of timed lights, which are not as good (in my opinion) when compared to sensor-activated lights.


Some timed lights may be set at a specific interval, like 30 seconds, or even be synchronized to turn green in what’s called a “wave” from intersection to intersection, this way the driver should ideally make it through multiple intersections without stopping.

Other intersections make use of inexpensive cameras—not those evil speed trap, taxpayer money-grabbing fiends—that monitor the lanes to detect when a car has pulled up. If this is the case, you should make sure you place the car far enough forward for the camera to see you without affecting pedestrian crosswalks or just straight up sitting in the middle of the intersection.

Just get the nose of your car right up to that big, bold white line (and not three feet behind it; you don’t have to see the line and you should be able to judge where the front of your car is and it is very annoying if you don’t, thanks). Sometimes I stop early so I can repeatedly pull forward a few inches, which may actually help the camera sense your vehicle’s motion and may get you going sooner. For me, it’s just something to do to pass the time.

Many intersections make use of underground sensors, which you can usually spot because the pavement looks like a finished puzzle of really ugly shapes carving up the lane. This type of sensor is called an “induction loop” and uses a wrapped coil buried under the road with flowing electricity. The electricity in the wire creates a magnetic field large enough to detect when the metal of a car or motorcycle passes into the field from above.


So, maybe now you have a better idea of why you’ve been sitting through three light cycles and have seen the jogger pass by twice already. That’s because you are doing something wrong, maybe, probably.

Also—it doesn’t help anybody to honk at the car in front of you the moment the light turns green. Nobody likes that. Seriously, stop it. Otherwise I’m going to slam on my brakes and make you wait another cycle until you pull out a baseball bat and I have to run the red.


Happy traveling.

Reviews Editor, Jalopnik

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You get a solid, one-one-thousand, two-one-thousand, three-one-thousand count. If you haven’t started moving, or your brake lights haven’t at least flickered off by then, you get the horn.

The person at the head of the line has a moral and societal responsibility to get their ass rolling because there are people behind them.