# Traffic signals not sensing my hybrid. Is this possible? **URL:** \ **Category:** Factual Questions\ **Created:** [August 31, 2012, 3:42pm UTC](https://boards.straightdope.com/t/traffic-signals-not-sensing-my-hybrid-is-this-possible/633268 "2012-08-31T15:42:53Z")\ **Posts on this page:** 16\ **Page:** 3
**Author:** ![jz78817](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jz78817/32/1028_2.png) [@jz78817](https://boards.straightdope.com/u/jz78817)\ **Post date:** [September 4, 2012, 12:15am UTC](https://boards.straightdope.com/t/traffic-signals-not-sensing-my-hybrid-is-this-possible/633268/41 "2012-09-04T00:15:34Z")
since when does the Insight have a frame? ---
**Author:** ![Really\_Not\_All\_That\_Bright](https://avatars.discourse-cdn.com/v4/letter/r/e8c25b/32.png) [@Really\_Not\_All\_That\_Bright](https://boards.straightdope.com/u/Really_Not_All_That_Bright)\ **Post date:** [September 4, 2012, 12:18am UTC](https://boards.straightdope.com/t/traffic-signals-not-sensing-my-hybrid-is-this-possible/633268/42 "2012-09-04T00:18:50Z")
I assumed he meant the (uni)body. ---
**Author:** ![jz78817](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jz78817/32/1028_2.png) [@jz78817](https://boards.straightdope.com/u/jz78817)\ **Post date:** [September 4, 2012, 12:37am UTC](https://boards.straightdope.com/t/traffic-signals-not-sensing-my-hybrid-is-this-possible/633268/43 "2012-09-04T00:37:21Z")
which Insight does **davidm** have? ---
**Author:** ![davidm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/davidm/32/225_2.png) [@davidm](https://boards.straightdope.com/u/davidm)\ **Post date:** [September 4, 2012, 12:41am UTC](https://boards.straightdope.com/t/traffic-signals-not-sensing-my-hybrid-is-this-possible/633268/44 "2012-09-04T00:41:07Z")
It’s a 2010 Insight EX. ---
**Author:** ![Muffin](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/muffin/32/4341_2.png) [@Muffin](https://boards.straightdope.com/u/Muffin)\ **Post date:** [September 4, 2012, 12:55am UTC](https://boards.straightdope.com/t/traffic-signals-not-sensing-my-hybrid-is-this-possible/633268/45 "2012-09-04T00:55:18Z")
> [@Leo\_Bloom](#): > > What’s the name of that Cary Grant movie like this? Topper ---
**Author:** ![jz78817](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jz78817/32/1028_2.png) [@jz78817](https://boards.straightdope.com/u/jz78817)\ **Post date:** [September 4, 2012, 1:15am UTC](https://boards.straightdope.com/t/traffic-signals-not-sensing-my-hybrid-is-this-possible/633268/46 "2012-09-04T01:15:15Z")
> [@davidm](#): > > It’s a 2010 Insight EX. so the body and structure are mostly steel. ---
**Author:** ![njtt](https://avatars.discourse-cdn.com/v4/letter/n/ecd19e/32.png) [@njtt](https://boards.straightdope.com/u/njtt)\ **Post date:** [September 4, 2012, 1:38am UTC](https://boards.straightdope.com/t/traffic-signals-not-sensing-my-hybrid-is-this-possible/633268/47 "2012-09-04T01:38:22Z")
> [@Leaffan](#): > > So you think a timer toggling “red” “green” “red” “green” ad infinitum is better than a loop sensor that actually senses when traffic needs to merge? For the purpose at hand - spacing out cars so they don’t try to enter the freeway all in a bunch - yes. Better in the sense of more reliable and equally as effective. Clearly, as the OP shows, sensor-based systems are _not_ very reliable, and cause unnecessary hold-ups when the sensor fails to trigger. As I said, I am fairly sure the on-ramp lights in the L.A. area do work on a timer, and they work fine. They are not on all day, of course, only when traffic on the freeway is heavy. Possibly the timed light system is put into operation by some sort of sensor system on the freeway itself (but my guess would be that it is actually switched on according to time of day and knowledge and observation of traffic patterns). ---
**Author:** ![davidm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/davidm/32/225_2.png) [@davidm](https://boards.straightdope.com/u/davidm)\ **Post date:** [September 4, 2012, 1:43am UTC](https://boards.straightdope.com/t/traffic-signals-not-sensing-my-hybrid-is-this-possible/633268/48 "2012-09-04T01:43:16Z")
> [@jz78817](#): > > so the body and structure are mostly steel. Which should trigger an induction loop, right? ---
**Author:** ![davidm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/davidm/32/225_2.png) [@davidm](https://boards.straightdope.com/u/davidm)\ **Post date:** [November 9, 2012, 9:33pm UTC](https://boards.straightdope.com/t/traffic-signals-not-sensing-my-hybrid-is-this-possible/633268/49 "2012-11-09T21:33:42Z")
Just to follow up on this, if anyone’s interested: The ramp signals haven’t been on again until recently. Over the last week or two they were on several times in the morning. They worked correctly for me every time. So I guess whatever the problem was has been solved. Either they changed something or I overcame whatever stupidity was afflicting me and stopped in the right spot this time. ---
**Author:** ![Asimovian](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/asimovian/32/172_2.png) [@Asimovian](https://boards.straightdope.com/u/Asimovian)\ **Post date:** [November 9, 2012, 11:42pm UTC](https://boards.straightdope.com/t/traffic-signals-not-sensing-my-hybrid-is-this-possible/633268/50 "2012-11-09T23:42:04Z")
> [@njtt](#): > > As I said, I am fairly sure the on-ramp lights in the L.A. area do work on a timer, and they work fine. They are not on all day, of course, only when traffic on the freeway is heavy. Possibly the timed light system is put into operation by some sort of sensor system on the freeway itself (but my guess would be that it is actually switched on according to time of day and knowledge and observation of traffic patterns). The sensors at the onramp lights do NOT cycle green/red when there is no traffic waiting. This, and the rest of what I have to say, is based on observation, and not from a specific cite, but I can try to find one if you want. The lights are on timers so that they are only operating during certain hours of the day, generally rush hours. Once they are turned on, they are either steady green (based on traffic flow as measured by sensors on the freeway itself), or, if traffic is heavy enough, they stay red until a car is sensed on the onramp. ---
**Author:** ![Leaffan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/leaffan/32/299_2.png) [@Leaffan](https://boards.straightdope.com/u/Leaffan)\ **Post date:** [November 10, 2012, 1:48am UTC](https://boards.straightdope.com/t/traffic-signals-not-sensing-my-hybrid-is-this-possible/633268/51 "2012-11-10T01:48:23Z")
> [@davidm](#): > > Just to follow up on this, if anyone’s interested: The ramp signals haven’t been on again until recently. Over the last week or two they were on several times in the morning. They worked correctly for me every time. > > So I guess whatever the problem was has been solved. Either they changed something or I overcame whatever stupidity was afflicting me and stopped in the right spot this time. I think maybe they had to reverse the polarity of the flux capacitor in the sensor loop buffer. Glad to hear to worked for you. ---
**Author:** ![davidm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/davidm/32/225_2.png) [@davidm](https://boards.straightdope.com/u/davidm)\ **Post date:** [November 10, 2012, 1:53am UTC](https://boards.straightdope.com/t/traffic-signals-not-sensing-my-hybrid-is-this-possible/633268/52 "2012-11-10T01:53:17Z")
Flux capacitor? I guess I better make sure not to go down that ramp at 88 MPH, or maybe I should and have an adventure! Hmm… ---
**Author:** ![goldmund](https://avatars.discourse-cdn.com/v4/letter/g/a4c791/32.png) [@goldmund](https://boards.straightdope.com/u/goldmund)\ **Post date:** [November 10, 2012, 3:18am UTC](https://boards.straightdope.com/t/traffic-signals-not-sensing-my-hybrid-is-this-possible/633268/53 "2012-11-10T03:18:12Z")
I can see one advantage for a sensor based ramp meter setup. Some vehicles will take longer to accelerate than others, and take up more roadway. If the system’s smart enough, it could detect the larger vehicle, and give it a longer green cycle, waiting for it to clear the lane before letting the other lane go. ---
**Author:** ![davidm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/davidm/32/225_2.png) [@davidm](https://boards.straightdope.com/u/davidm)\ **Post date:** [November 10, 2012, 3:47am UTC](https://boards.straightdope.com/t/traffic-signals-not-sensing-my-hybrid-is-this-possible/633268/54 "2012-11-10T03:47:33Z")
> [@goldmund](#): > > I can see one advantage for a sensor based ramp meter setup. Some vehicles will take longer to accelerate than others, and take up more roadway. If the system’s smart enough, it could detect the larger vehicle, and give it a longer green cycle, waiting for it to clear the lane before letting the other lane go. The ramp I’m talking about is single lane. It’s purpose is to space out the vehicles entering the traffic flow. ---
**Author:** ![Magiver](https://avatars.discourse-cdn.com/v4/letter/m/4491bb/32.png) [@Magiver](https://boards.straightdope.com/u/Magiver)\ **Post date:** [November 10, 2012, 5:17am UTC](https://boards.straightdope.com/t/traffic-signals-not-sensing-my-hybrid-is-this-possible/633268/55 "2012-11-10T05:17:37Z")
> [@davidm](#): > > I don’t think there are cameras. At least I hope not. If there are I already have 3 violations. > > They’ll probably be active tonight. I’ll make sure that I’m sitting in the right place. > > The gas engine on an insight is smaller than normal, but you’d think that all the metal under the hood would trigger it regardless. Cameras don’t equal speed trap. They’re also used in place of metal detectors for traffic signal triggers. They probably look for changes in a grid pattern and interpret it as an object that is moving or has moved to the front of the intersection. They should allow for programming that recognizes different traffic patterns and adjust the lights accordingly. In your case, it’s one car, one green light. It’s probably a metal detector. It’s an interesting conjecture to consider that the magnetic field thrown by a hybrid motor would mess with the signal but that implies it’s running. Is this an automatic transmission that will hold the car on a hill or does the engine shut off requiring you to brake? ---
**Author:** ![XRaeth](https://avatars.discourse-cdn.com/v4/letter/x/f14d63/32.png) [@XRaeth](https://boards.straightdope.com/u/XRaeth)\ **Post date:** [November 10, 2012, 6:05am UTC](https://boards.straightdope.com/t/traffic-signals-not-sensing-my-hybrid-is-this-possible/633268/56 "2012-11-10T06:05:47Z")
> [@davidm](#): > > Flux capacitor? I guess I better make sure not to go down that ramp at 88 MPH, or maybe I should and have an adventure! Hmm… Well as long as your car isn’t producing three point twenty one Giga Watts of power you should be fine :). [Previous page](https://boards.straightdope.com/t/traffic-signals-not-sensing-my-hybrid-is-this-possible/633268.md?page=2)