Insufficient Feromagnetic Content

[CTX-SLPR]

Just a fancy way of saying not enough iron and steel. I swear the car doesn't have enough ferromagnetic material to trip the magneto inductive sensors in the road for stop lights. I keep sitting at them for like 8 light cycles until someone pulls up behind me then it trips! Anyone else have this problem?

 

[owlman]

Wow, never had that problem myself. I think those loop sensors will detect any large metal object, it doesn't have to be magnetic. And the LS certainly has a lot of metal (most of it magnetic anyway). Maybe you're just pulling up too far?

 

[CTX-SLPR]

They'd have to be pretty sensative to pickup the inducted feild off of the aluminum. Changing magnetic fields create electrical fields, you are essentially driving a magnet (abiet not very powerful of one) across the current loop which you would use to detect the generated field.

 

[mharrison]

You don't have like 30" wheels on it do you?

 

[postalUT]

In some states (TN for example) you are allowed to legally run a red light provided that the intersection is completely clear and the light has cycled through twice. It's basically a workaround for sport bikes with all fiberglass components.

As far as fixing the problem, go to your local sport bike shop. There are kits intended for sport bikes that increase detectability by those sensors. See if you could retrofit it for your LS. Besides that, nothing really much you can do.

 

[nickandersonLS01]

It happens to me at 2/5 stop lights on my way to/from work, I never knew how the sensors worked I just figured the 2 were broken(especially when I'm the only one at the light for 5 minutes, and I back up and go forward again and it still doesn't change) then someone will come from the other way and it will change.... so how exactly do the sensors work?

 

[luttersj]

In some states (TN for example) you are allowed to legally run a red light provided that the intersection is completely clear and the light has cycled through twice. It's basically a workaround for sport bikes with all fiberglass components.

As far as fixing the problem, go to your local sport bike shop. There are kits intended for sport bikes that increase detectability by those sensors. See if you could retrofit it for your LS. Besides that, nothing really much you can do.

As a sport bike rider, don't waste your money. They do nothing to help trigger the sensors.

MN has a law just like the one that you mentioned. I know about because of the sport bike thing. I've never had a problem triggering one in my car, though.

 

[luttersj]

It happens to me at 2/5 stop lights on my way to/from work, I never knew how the sensors worked I just figured the 2 were broken(especially when I'm the only one at the light for 5 minutes, and I back up and go forward again and it still doesn't change) then someone will come from the other way and it will change.... so how exactly do the sensors work?

From what I understand, a current runs though wires buried into the pavement. When a magnetic object (not aluminum) crosses it the signal is broken and it triggers the light cycle.

Is it possible to try the same light in another vehicle or ask your neighbors if they've had similar experiences? Maybe it is defective....

 

[owlman]

What I've read is that it just has to be metal or something conductive. Like a metal detector can detect non-magnetic stuff too. Maybe the old ones worked differently.

 

[CTX-SLPR]

Any metal has a magnetic field, they just won't retain it permenantly like a feromagnetic metal will which as a straight metal is just Iron and Nickel that I can think of off the top of my head. The sensor works as I understand them by sensing the difference in current though the loop caused by the moving metal in the magnetostatic field generated by the current generating a back EMF. Basically the feild trys to return to static causing a change in the current to equalize the magnetic field again. Again this isn't because I've designed one, its how I understand how they work based on the way the behave. Feromagnetic metals will have a stronger EMF due to the higher magnetic permability, sigma.

 

[Eric0508]

i doubt its your car, its probably something wrong with the sensor. Think of all the cars that would have problems with the system. Tons of cars have high aluminum content and carbon fiber content and plastic(corvette's bmw's, mercedes', jaguar's, some saturns have dent resistant plastic body panels), as well as even aluminum frames (new corvette). Plus trucks with high lifts also probably wouldn't trip it. Besides, the metal that is closest to the sensor is probably the iron frame. Thats my theory anyways.

 

[CTX-SLPR]

I might try it in my Riviera which is solid steel and my Regal which has a fair bit of plastic body panels.

 

[SoonerLS]

The LS has a higher percentage of 'loomnum construction than pretty much anything this side of the new Jags, but I suspect the sensor is defective. Heck, we have some sensors here that will trip when a freaking bicycle rides over the sensor loop, and I've never had a problem with sensors while driving either of my LSes...