Pulsing brake lights on new vehicles

[RossABQ]

For many years now (say 10 or more) I have seen what appear to be brand new cars with the high-mounted brake light pulsing, while the main brake lamps do not, at a rate of maybe once per second when the brakes are applied. This pulsing seems to stop after the cars are a month or two old, or maybe it's a mileage thing. I've also seen some (but much fewer) relatively new cars do this, making me wonder if they were just reset, i.e., new PROM or ECU, something like that.

Please tell me I'm not imagining this! and what purpose it serves? Some kind of study? To tell you the truth, I like the idea of pulsing HM lights, but if all cars did it all the time, it would get annoying pretty quickly in heavy traffic.

 

[evelrod]

I don't recall seeing any "pulsing brake lights" on cars here in Socal, lately. I have a guy on a Harley that passes me in the mornings that has a pulsing headlight and a brake light that goes amber when he backs off the throttle. The red brake light pulses faster as he applies more brake. First saw him several years ago. The brake light deal, amber/red, sounds doable for a car, the pulsing headlight kinda bothers me, though.

Rod

 

[IRstuff]

Then it's doing its job:

http://www.pashnit.com/product/signal_dynamics.html

The intent is to make it more obvious that you've got a jack^$$ about to snake you. They like being in front of the pack, but not going at the speed required to maintain that position.

TTFN
faq731-376

 

[patprimmer]

I have also seen evidence that improved dynamic safety features in a car end up reducing travel time rather than decreasing accidents as drivers readjust to the same safety margin. I think the dat was to do with ABS.

Certainly more distractions and a fashion statement of heavy window tints counters some safety devices.

Regards
Pat
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[msquared48]

Pat:

I pump the brake pedal whether the guy behind me is awake or not. We were hit from behind (notice I did not say rearended here) back in '77 by a person doing 55 when I was stopped. Do not want to go thru that again.

Mike McCann
MMC Engineering

http://mmcengineering.tripod.com

 

[evelrod]

Mike, I've also had the misfortune of being whacked by an errant Chrysler while sitting at an intersection in Long Beach in my little Lotus Cortina. The only saving, such as it was, was that I was sitting with the car in gear waiting for the light to change when I saw this giant three ton 'turd' coming at me. I launched my car like at the drag strip. Still hit me but the impact was mitigated a bit by my efforts. Still totaled a very expensive little car and GEICO needed several years and a good bit of prompting from the courts to pay their share which was nowhere near enough.

I'm with you. Not something I need to repeat.

Rod

 

[IRstuff]

I got rear-ended in the return line of a rental company. Pumping the brake wouldn't have mattered, since that person was busy rummaging around for the rental agreement instead of watching where they were going. Sometimes, you cannot escape your fate.

TTFN
faq731-376

 

[SomptingGuy]

I'm rethinking my braking behaviour. Even though I think that brakes are for losers with no forward planning (unless in racing conditions), should there be a "I'm off the gas indicator"?

- Steve

 

[RossABQ]

5 years ago I was 4th or 5th in line at a stoplight that had just turned green, in th emiddle of three lanes. I had just taken my foot off the brake, and was just barely moving. I was in a Chevy C1500 exteneded cab longbed that weighed 5600#. A guy slammed into my rear at 40 mph in a Grand Cherokee, because he was busy dialing his cell phone to notice I wasn't moving, there were no brake lights lit on any of the cars. My truck was old enough that it did not have headrests, so my head snapped back completely horizontal. 5 years later my neck is finally pretty normal. (BTW, he had a suspended license due to multiple DUI's, no insurance, no registration, and was unemployed)

No fancy safety features would have done as much as a simple headrest. Although a collision detection system that fired a rocket propelled grenade into his Jeep sounded pretty good at the time.

 

[IRstuff]

That wouldn't have mattered to some degree. By the time a targeting system decides that the car is, in fact, a threat, the RPG would detonate too close to your car, and the remaining bits of the OPFOR would still be coming at you only slightly slower, albeit, with less damage potential.

A transporter beam would be way more useful. Your guy could have been dropped off in Timbuktu or similar.

TTFN
faq731-376

 

[RossABQ]

Don't discount the personal satisfaction aspect..

 

[IRstuff]

There is that ;-)

TTFN
faq731-376

 

[pontiacjack]

Since we're already somewhat off-topic from the original question, and some general discussion of brake lights has begun:

An accident a few years ago makes me think that, yes, something less crude than brake lights would help. On a rainy night my son was following another car as they approached a curve (familiar to both drivers). Out of view of my son, a dog ran in front of the other car- whose brake lights had already been lit for awhile. No car occupants (nor the dog) were injured in the ensuing collision, nor was there much vehicle damage. But I imagine that some type of "decceleration signal" might have helped avoid this collision.

 

[pontiacjack]

... 'deceleration'... should have used spell-check!

 

[NormPeterson]

. . . whose brake lights had already been lit for awhile . . .

That right there is part of the problem. When somebody uses the brake to modulate speed to down around the ±1 mph level, to control following distance to ± a foot or two, or needlessly rests their foot on the brake pedal going through a curve instead of getting slowed down the necessary amount first - a following driver isn't going to immediately know when the leading driver suddenly gets serious about stopping.

Whether pulsing brake lights above some threshhold would be a real solution or just a temporary one until people start disregarding the steady brake light illumination is a separate matter.

It's a lot easier to trust the driver who uses the brakes harder but only when stopping or slowing significantly.

I'm sure that in addition to operator inexperience in this specific case, consumer transmission preference and mandated efforts at reducing fuel usage deserve some share of the blame.


Norm

 

[evelrod]

There is the "nothing new in the automotive world" aspect in all this. It seems all this anti collision, brake light "whatever" has been done several times by various well intended individuals/companies. The high mounted brake light, 1930's, the pulsing brake light, 1940's, the amber deceleration light, 1950's, etc, etc. I had a neighbor that drove a '38 Buick with a system of red, green and, amber lights arranged across the rear window. Green, on the power. Red, brakes. Amber off the throttle... and that was in the mid 50's. I still see the dude on the BMW that has a pulsing brake light, faster the harder the application of brake. I have not seen any (thankfully) pulsing headlights lately, though.

I've mentioned that I live a few blocks from a high school and that means I get to see possibly a bit more troublesome driving/texting/phoning/horseplay/giggling inattentive driving habits. None of which would be mitigated even one tiny little bit by any of the "brake light solutions" spoken of in this thread. Hell, I nearly got creamed by a teen that was turned completely around facing the back seat!!!

Rod-----gettin' too old for this crap.

 

[btrueblood]

"I have not seen any (thankfully) pulsing headlights lately, though."

There's some kind of bikes (BMW maybe? Others?) that have pulsing headlights. Very annoying. I'm sure the intent is to "enhance visibility", but there are times that I wonder if oncoming drivers wouldn't fixate on the pulsing light and plow right into them.

 

[dgallup]

I think all the pulsing motorcycle headlights are aftermarket addons.

----------------------------------------

The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

 

[benta]

Or faulty voltage regulators...

Benta.

 

[PEW]

The driver's handbook of my recently acquired 2008 Volvo S40 D5 (UK model) says if the ABS activates, the brake light pulses.

So far I've only managed to try out the ABS once and that was when a large hare ran out from the hedge at 5:45 a.m on a single track road. Just missed it, by a hare's breath (yes, I know that's not the actual saying, but ..).

There was no-one else stupid enough to be driving to work that early so there are no evidential reports from following drivers, to say if it did pulse, or not.

 

[patprimmer]

You mean you did not look in the rear view mirror for reflected glow from the brake lights.

Regards
Pat
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