4 ms·

> BMW’s dynamic brake light, for example, flashes during emergency braking to alert trailing drivers, greatly enhancing road safety. Mind you, that this is not

> BMW’s dynamic brake light, for example, flashes during emergency braking to alert trailing drivers, greatly enhancing road safety. Mind you, that this is not enabled in all countries. In the USA the rear fog lights turn on in addition to the brake lights under heavy braking, as flashing the lights weren't allowed. They remain on until you no longer depress the brakes. Unsure if they're allowed right now, or whether the ones you see are aftermarket mods. For BMW you can change the coding (configuration) relatively easy. There is also a difference in 3 flashes when you touch the brakes, constant flashing while pressing the brakes, or only flashing under having braking. I can't imagine driving in stop&go traffic where all brake lights are constantly flashing.

mygnu 1y ago
only flashes on heavy braking, normal use is not affected
- jajko 1y ago
  I dont understand why exactly this isnt mandatory for past 2 decades in regulated markets like EU. Over easter I had the displeasure of driving cca 1500km road with family and we experienced quite a few 130kmh -> full stop without warning situations that one barely manages even when breaking full and heavily relies on all others doing the same. In one of the situations a car right in front of us didnt manage and hit already-crashed cars in front of it in billiard style, plastics and glass flying everywhere, luckily nobody was injured but cars were in pieces. Second case next day - again full stop out of blue, ahead, we & after us managed within 3-4m of each other, but cars after that didnt, again billiard that travelled all the way up to us (we ended up with few scratches on back spoiler, I moved our car a bit ahead when I heard big bangs behind, avoiding bigger damage to us). One only has a split second to realize how quickly that car ahead is closing in in such scenarios if you dont have other info. Could save hundreds of lives each year easily and easy to implement.
  - HeyLaughingBoy 1y ago
    US mandated automatic emergency braking starting in 2029.
abfan1127 1y ago
my US mazda cx5 center brake light flashes when you press the brakes.
- wolrah 1y ago
  > my US mazda cx5 center brake light flashes when you press the brakes. That is not a factory feature, it's almost certainly a dealer-installed piece of junk like this (https://pulseprotects.com/product-info/ https://pulseprotects.com/product-info/) which the dealer almost certainly charged a stupid amount of money for, and as noted it's not actually legal in the US. Around me the local Hyundai/Kia chain loves to install those, and I hate them.
  - Muromec 1y ago
    Doesn't seem to be illegal enough if dealers are installing them
    - mschuster91 1y ago
      No one cares, not all states have mandatory inspections, and many inspectors just check if the brake light comes on when they press the brake pedal which would not reveal such an aftermarket device. The only way to catch something like this would be a road driving test by the inspector, and even here in Europe this is not required.
    - teqsun 1y ago
      IIRC in the USA there are features allowed to be installed aftermarket that aren't legal to be installed as a dealer option (like front side-window tinting)
    - toast0 1y ago
      I've got a NHTSA letter bookmarked [1] that says > According to a document by SafeLite of America, Inc., that you enclosed, its product Safe-T-Stop "will pulse [the center high mounted brake light] for approximately 6 seconds and reactivate if the brakes are reapplied." You read S5.5.10(d) of Federal Motor Vehicle Safety Standard No. 108 as requiring "that the third brake light must be wired to be steady-burning," and that you believe that Safe-T-Stop "contravenes this requirement of the standard by varying the brightness of the light." > We confirm your interpretation. S5.5.10(a), (b), and (c) list the motor vehicle lamps that may flash when they are operated. No stop lamp is among the lamps listed. S5.5.10(d) requires all other lamps to be wired to be steady burning, thus including all stop lamps. Standard No. 108 does not allow a stop lamp that pulses, and a vehicle with a stop lamp that pulses does not meet Federal requirements. It's clear that there's not much enforcement, since all the dealers I've visited near me install these things by default. If you commit to a car that's not yet delivered, you can negotiate to exclude these, or you can have them remove it (but they'll most likely have cut into the factory harness to install it, so the wiring harness has been modified, which is a negative IMHO). Personally, I find these devices to be pretty terrible. I would be fine with flashing for high intensity braking, but the flashing is attention grabbing by design, and it's inappropriate in a lot of situations as it distracts from gathering awareness of the surroundings. [1] https://www.nhtsa.gov/interpretations/20288ztv https://www.nhtsa.gov/interpretations/20288ztv

mygnu 1y ago

only flashes on heavy braking, normal use is not affected

jajko 1y ago
I dont understand why exactly this isnt mandatory for past 2 decades in regulated markets like EU. Over easter I had the displeasure of driving cca 1500km road with family and we experienced quite a few 130kmh -> full stop without warning situations that one barely manages even when breaking full and heavily relies on all others doing the same. In one of the situations a car right in front of us didnt manage and hit already-crashed cars in front of it in billiard style, plastics and glass flying everywhere, luckily nobody was injured but cars were in pieces. Second case next day - again full stop out of blue, ahead, we & after us managed within 3-4m of each other, but cars after that didnt, again billiard that travelled all the way up to us (we ended up with few scratches on back spoiler, I moved our car a bit ahead when I heard big bangs behind, avoiding bigger damage to us). One only has a split second to realize how quickly that car ahead is closing in in such scenarios if you dont have other info. Could save hundreds of lives each year easily and easy to implement.
- HeyLaughingBoy 1y ago
  US mandated automatic emergency braking starting in 2029.

abfan1127 1y ago

my US mazda cx5 center brake light flashes when you press the brakes.

wolrah 1y ago
> my US mazda cx5 center brake light flashes when you press the brakes. That is not a factory feature, it's almost certainly a dealer-installed piece of junk like this (https://pulseprotects.com/product-info/ https://pulseprotects.com/product-info/) which the dealer almost certainly charged a stupid amount of money for, and as noted it's not actually legal in the US. Around me the local Hyundai/Kia chain loves to install those, and I hate them.
- Muromec 1y ago
  Doesn't seem to be illegal enough if dealers are installing them
  - mschuster91 1y ago
    No one cares, not all states have mandatory inspections, and many inspectors just check if the brake light comes on when they press the brake pedal which would not reveal such an aftermarket device. The only way to catch something like this would be a road driving test by the inspector, and even here in Europe this is not required.
  - teqsun 1y ago
    IIRC in the USA there are features allowed to be installed aftermarket that aren't legal to be installed as a dealer option (like front side-window tinting)
  - toast0 1y ago
    I've got a NHTSA letter bookmarked [1] that says > According to a document by SafeLite of America, Inc., that you enclosed, its product Safe-T-Stop "will pulse [the center high mounted brake light] for approximately 6 seconds and reactivate if the brakes are reapplied." You read S5.5.10(d) of Federal Motor Vehicle Safety Standard No. 108 as requiring "that the third brake light must be wired to be steady-burning," and that you believe that Safe-T-Stop "contravenes this requirement of the standard by varying the brightness of the light." > We confirm your interpretation. S5.5.10(a), (b), and (c) list the motor vehicle lamps that may flash when they are operated. No stop lamp is among the lamps listed. S5.5.10(d) requires all other lamps to be wired to be steady burning, thus including all stop lamps. Standard No. 108 does not allow a stop lamp that pulses, and a vehicle with a stop lamp that pulses does not meet Federal requirements. It's clear that there's not much enforcement, since all the dealers I've visited near me install these things by default. If you commit to a car that's not yet delivered, you can negotiate to exclude these, or you can have them remove it (but they'll most likely have cut into the factory harness to install it, so the wiring harness has been modified, which is a negative IMHO). Personally, I find these devices to be pretty terrible. I would be fine with flashing for high intensity braking, but the flashing is attention grabbing by design, and it's inappropriate in a lot of situations as it distracts from gathering awareness of the surroundings. [1] https://www.nhtsa.gov/interpretations/20288ztv https://www.nhtsa.gov/interpretations/20288ztv