Are brake lights required? Maybe Hyundai points to FMVSS and says - not so fast.

[3DDave]

Just found this gem:

https://www.youtube.com/watch?v=U0YW7x9U5TQ

Nothing like a standard that cares about what pedal is being pushed and not what the car is doing or what the driver is requesting. And for once Europe is farther behind on safety regulation than the US. How the heck did that happen?

Noting that this same problem exists in manual transmission cars, allowing significant slowing without brake lights, it doesn't seem like the solution is to make the situation worse on the new tech when the old tech is drying up and going away.

 

[Factoter]

Big rigs don’t apply stoplights with the Jake Brakes, but some RV’s do. The driver should positively control the stoplights, otherwise it can provoke an incident; and while the reverse situation may also be true, an experienced driver will prefer to control vehicle stoplights.

 

[BrianPetersen]

All decent modern electric cars, including mine, apply the brake lamps whenever a certain threshold of deceleration is exceeded, over and above whether that's due to the driver pressing the brake pedal (i.e. the internal logic is "brake pedal is being pressed OR certain rate of decel exceeded OR vehicle is being held stopped by hill-hold logic"). Clearly there are still some holes in the logic in some cars, but most of them lately have been getting this more-or-less right even though the situation is not addressed in the motor vehicle standards.

 

[Factoter]

I think my take, that regen activated brake lamps are potentially dubious, is too simplistic, This can’t be pigeonholed into whimsies of an experienced driver, versus, *somebodies granny is driving that car* arguments(unnecessary braking). Rather, proverbial *nanny-state* is looking to the credulous millennial driver, their faces permanently planted to some device, like spots on a leper. So, queue the return of the emergency brake . . . Lol

https://www.aftermarketnews.com/nht...tic-emergency-braking-on-light-duty-vehicles/

* AEB systems would result in significant reductions in property damage caused by rear-end crashes*

But on second thought, brake lamps are simply an inconvenience for optimization of SOC, maybe that’s the real reason?

 

[BrianPetersen]

So your take is that brake lamps should NOT be applied during regenerative braking?

Safety devices (i.e. brake lamps) should be automatic to the extent that can practically be achieved, and nowadays, it's very easy to put additional conditions into the brake-lamp control logic. This is not a "nanny state" situation. Regenerative braking has introduced a situation that was not anticipated when the standards were written, and that clause in the standard concerning brake lamps dates back many decades.

Maybe brake lamps should be activated when a jake brake or exhaust brake is in use.

 

[Factoter]

Hello BrianPetersen. Should regen have brake lamps? Yes. No. Maybe. It’s a firm fifty-fifty.
The car in question above, is motoring down the freeway by itself, unsupervised. In fact the car is supervising the erstwhile driver, that he is semi comatose. In this situation where the car is the driver, and the driver is cargo, what are signal lamps for? It seems that confusion on this subject, *that’s not fair, that’s not right* is only hastening the impossible conclusion —- fully autonomous killer robots. Please excuse the tongue-in-cheek.

 

[BrianPetersen]

Brake lamps and signal lamps (and headlights) are required on hypothetical self-driving vehicles, and even on vehicles that aren't self-driving but have automatic emergency braking, for the very simple reason that for the foreseeable future, they share the roads with other vehicles that are not so equipped.

We have powered vehicles today which don't have brake lamps or turn signals and have never had them: Trains! But they have physical separation where practical, and really loud horns, and in many cases automated barriers and warning systems, where they have to interface with other transport systems.