Yesterday, our pals over at The Drive published an article with the headline “Even the Cybertruck’s Brake Lights Don’t Make Sense,” and while I enjoy poking fun at the Cybertruck as much as the next guy (unless that next guy is the one who thinks the Cybertruck will be “the best product the world has ever seen”) in this case I think the criticism is a bit unfair. I don’t think the Cybertruck’s brake lights are bad; in fact, while they’re hardly perfect, I actually think they do a pretty admirable job of what the whole raison d’etre of a brake lamp is: getting your attention. So, since these have been called out, let’s take a deeper look at the Cybertruck brake lights.
I’ve actually addressed these brake lamps before, in a previous Cybertruck story from the beginning of the month, where I included this little video clip of the brake lights in action:
Another look at @Tesla Cybertruck brake lights, what do you think? pic.twitter.com/TEVzUIPk5O
— Dirty Tesla (@DirtyTesLa) October 2, 2023
Here’s what I said about the brake lights then:
“What I like about this brake lamp approach is that there is a clear shift both in lamp brightness, as is traditional, but also in the visual graphic of the lamps themselves, switching from one long unbroken bar into three bright elements, and I think that does a lot to capture the driver’s attention. It’s also interesting how pretty much all of the main taillights are at the high level of the center-high-mount stop lamp (CHMSL), so they’re all on the same linear plane. It seems to work well.”
And, I stand by that!
Now, in The Drive story, this video is included, with its associated commentary:
Interesting that they don’t put another 3rd brake light on top of the rear glass like they did with the Baja light bar in front. Imagine if the tailgate was down, you’ll only see the two side, honestly don’t know if that’s enough light especially if it’s a foggy night pic.twitter.com/7ga77rwcls
— omg_Tesla/Rivian (@omg_tesla) October 25, 2023
The issue seems to be that during braking, the light pattern changes from the one long taillight bar to a three-segment setup, with a pair of bright square lights at either side and a bar in the middle. I believe this is done to emulate the three-brake-lamp setup required by law, with a center high mounted stop lamp (CHMSL) and two brake lights. The concern about if that is “enough light” really shouldn’t be a concern, because there are federal standards that define a minimum size and brightness. For example, for the side stop lamps, they must be at least 7.75″ square inches in area, and the CHMSL must be at least 4.5″ square inches. So if this thing will be road legal, then it’ll be held to the same standards of light area as everything else on the road.
Here’s what The Drive has issue with regarding these lights:
The issue here is that less of the Cybertruck’s rear lighting is solely dedicated to brake lights than to the taillights or turn signals, the former of which deactivate during braking. Although the lights at the edges become more intense under braking, their small surface area means that overall, the Cybertruck emits less light when it’s slowing down. That’s pretty much the inverse of what drivers have come to expect. This could lead to drivers of following vehicles becoming confused, assuming a Cybertruck is coasting or accelerating when it’s braking, and vice versa. Best case scenario, the result is traffic flow problems; worst, rear-end collision.
Now, here’s why I don’t think this is a big deal: there’s not really less light being emitted, because the intensity of the brake lights themselves are significantly higher than the taillight bar, and that amount is set by legal standards as well. When the brake lights are activated, they’re essentially no different than any current car that has smallish taillights that re-purpose the taillight bulbs for brake lights, too. Look:
This setup really isn’t any different than, say, a Jeep, and I don’t see anyone writing about how Jeep brake lights don’t make sense. In fact, it’s likely better than how a car like the Jeep does it, in that the switch from not braking to braking is much more noticeable, as the taillight changes quite dramatically from one long bar to three very bright segments. On a car like the Jeep or any of the many other cars that share brake and taillight areas, all you have to go on is a change in brightness.
The Drive story also states
“However, the FMVSS does not appear to prohibit deactivating taillights during braking, so the Cybertruck’s taillights as seen here seem to be legal—even if they are perplexing, and potentially dangerous.”
…and they’re right, there are no regulations against de-activating taillights when brake lights are on, otherwise there would be millions of cars on the road made illegal, ranging from Dodge Neons to pre-’73 VW Beetles to Jeeps to AMC Hornets to Corvettes and the list goes on and on. With so many cars already on the road that do just this, I have trouble seeing how it can be perplexing or dangerous.
That said, designing taillights that way isn’t ideal! It was mostly done because, frankly, carmakers are cheapskates. Ideally, all the major taillight functions should have their own independent areas, so tail and brake and turn indicator and reverse lamp can all co-exist and illuminate in harmony, simultaneously as needed.
More crappy is that the Cybertruck has red rear indicators instead of amber ones. The look when off could have been kept the same by using red/amber LEDs, which exist. I think a better Cybertruck taillight setup could be like this, keeping in mind when the tailgate drops, brake/tail/turn have to all work in the outermost edge:
It’s also worth noting that if there are plans to export the Cybertruck outside of the US, it will be required to have amber rear indicators. So why doesn’t Tesla just suck it up and design them in now?
Just having the amber indicators there would help so much. With the tailgate down, the taillights can revert to the just red corner squares for stop/turn/tail, which is adequate, if not great.
That light bar could be used for all kinds of more advanced effects as well, seeing as how its essentially a very wide, narrow LED display. Flashing brake lamps for emergency stops, sequential indicators, all these things are possible! Here’s two examples: flashing brake lights for hard stops, and brake lights that grow as brake intensity increases:
Of course, if Tesla doesn’t want to put in that much effort, there is another cheap and proven option that could solve the complicated taillight issues, even with the tailgate down:
Slap a couple brackets and a pair of cheap box taillights on there: they’re good enough for Jeeps and pickups and millions of box trucks and 18-wheelers and delivery vehicles, so why wouldn’t they work here? They’re DOT-approved and you can get replacements in gas stations for like $20.
Remember, I love these things:
Overall, though, while I think there’s plenty of things to criticize the Cybertruck about, the brake lights just aren’t one of them. They’re not perfect, but they’re also no different than many cars already on the road, and, really, piling on about them just feels like trying to find something to complain about.
Look at me, defending the Cybertruck! Feels kinda weird.
Brake lights currently are pretty easy to figure out. Brake light is off – car is not braking. Brake light is on – car is braking. It’s simple. It works. Everyone knows what it means.
You throw in the Cybertruck lights and everything gets confusing. It’s always on. Is it always braking? Some of the light is off. Is it braking a little bit? What does the pattern mean? Drivers shouldn’t need to understand morse code to be able to figure out what message is being communicated.
Yeaaaahhh…. nah. I don’t buy the “other cars had crap brake light designs and they were legal so there’s no reason not to keep doing crap brake lights!” argument.
I won’t be long before every auto manufacturer wants to have their own Cool and Unique brake light designs. This manufacturer wants to have these segments always on, these always off, these bits sometimes. This other manufacturer wants to have all of the segments always on but under braking, they’re even more on! All in their own brand-specific pattern. Then they’ll be baking in animations and logos and god knows what else. A driver will need to know the morse code, semaphore and hieroglyphics for each specific car brand in order to decipher what is happening with the car in front.
That might sound ridiculous and hyperbolic but that’s the mission creep that will happen when automakers get too creative.
I’m happy with the current on/off binary solution. I just need to know if the car in front is braking or not.
US regulation doesn’t allow for that.
Allow for what?
Great. What am I supposed to do with a dirt bike in the back and that minuscule bed is forcing me to drive around with the tailgate down?
Replicate the strip along the top of the rear window.
Like I said over there, this is a truck designed by someone that doesn’t own, hasn’t driven nor has much experience with what pickup trucks are used for.
That’s OK, it’s designed for people who don’t use trucks as trucks.
The only time these will ever have anything large in the bed is when journalists/influencers are testing it
That video to me looks like the turn signals ARE amber. I’m not willing to spend the time to test that (with a screenshot and digital color meter), but I did replay it and squint, and I think that the right brake light is a different color to the left blinker. Certainly that would be smarter.
They could be bicolor LEDs in the tails and using GPS it knows where it is and automatically changes from red corners to amber corners.
Probably not…. but it’d be cool tho!
#TeamAmber
I would much prefer a “third-eye” light that *only* illuminates when braking, so that it’s obvious. I’ve been behind a lot of cars lately that it was hard to tell if their brake lights were on or not until the “third eye” lit up. This light, that just changes, could be confusing.
I do not see the CT when looking at your light simulations, its clearly a CYLON !!
I strongly suspect the most important lights on the Cybertruck will be the hazard flashers as they’re likely to be activated more than any of the others.
The bit I’m perplexed about is what happens when the tailgate is down? Are the tail/turn/brake lights attached to it and just face the ground when the gate is open? If we pretend that it’s an actual, useful truck it seems like occasionally someone would want to drive it with an oversized load and the gate down.
I could be missing something; I’d be hard-pressed to care less about this thing.
You all and your newfangled taillights and 3rd brake lights…
It was only a few years ago when Indiana finally clarified its law that you needed two red taillights on a car or truck.
Well into the early 2000s all you needed was a single taillight. In red or white. (WTF, Indiana, really??)
I had to memorize that when I used to hold a chauffeur’s license for in-state straight trucks.
Oh, and if your car, like any normal car from the last 90 years or so was equipped from the factory with two red taillights, they could still stop you for a taillight out or broken and showing a white bulb. ¯\_(ツ)_/¯
I agree with you. I can’t think of any vehicle with a CHMSL where there isn’t three separate segments of brightly illuminated lights when the brake is applied, with one clearly in the center. In other words, I can’t think of any case where the brake light is simply one large bar of light that spans the entire width of the vehicle, so there should be no reason to interpret a full bar of light spanning across the entire width as an indicator of braking.
Same story here on the Tesla, when the brakes are applied you get three separate segments of brightly illuminated lights, with one clearly in the center. IMHO the fact that the parking lights do span across the vehicle in a line, and that they convert to brake light functionalty is irrelevant. As a driver, if I see three separate bright lights illuminated with a clear separate center light, I interpret that as the brakes being applied. If I don’t see that (including if I see something else instead) the brakes are not being applied. Simple as that.
I have never once driven behind a vehicle that has illuminated full width tail lights like a late ’80s Buick Skylark or a new VW ID.4 and interpreted that as the vehicle in front having its brakes applied. Yes, I know it’s not an apples to apples comparison since those vehicles have the CHMSL in different locations, but my point still stands. Admittedly I’m an auto lighting nerd too (not to the level of Torch) who probably pays attention to this more than the average driver, but frankly if the Tesla’s lighting makes you clutch your pearls, you need to pay more attention while driving and try sucking less. I have the same feeling about a lot of safety nannies installed on newer cars, but fighting that at this stage is tilting at windmills.
And I say all this as someone who thinks the Cybertruck is completely pointless and will only be purchased by attention seeking chuds who I likely want nothing to do with.
But now when the LED bulbs inevitably fail at random intervals on this thing it’s going to look all fucked
It’s going to be like the Cadillac XLR where if the brake light fails, the car is totaled. Which will last longer, the taillights or the battery pack?
So the CHMSL *must* be mounted high, but no law says the other brake lights can not be mounted high. I’m thinking of the Chevy Express van, which has NO lights at eye level to most drivers. And there is plenty of precedent for mounting the CHMSL high on the tailgate of a truck, certain generations of Dodge Dakota did just that. Combining these two thoughts, I see nothing wrong here.
The GM Dustbuster vans (Trans Sport, Lumina APV, Silhouette) actually had the CHMSL mounted *below* the standard brake lights.
The taillights are indicative of the larger issue with the Cybertruck. In going for style over substance Elon has managed to achieve neither.
What happens with regen braking ? especially when set to max for 1 petal driving?
On my 3 it activates the brake lights when high regeneration is applied. I haven’t checked where the threshold though. I’d assume the same on the truck given the common code base.
Maybe the rear signals on modern electrics need to go from fluorescent green while they are accelerating, to white/amber when they are at cruise, progressing to orange, and then brighter and brighter red, as the regeneration/deceleration becomes more and more intense.
That would be spiffy, but the NHTSA is populated by folks that are just discovering fire and trying to figure out how to regulate it.
Low amounts of regen without the lights is just like engine braking.
> 1 petal driving
Is that when the flower in your New Beetle reaches its final moments?
Doh! Petal to the meddle!
I can’t trust anything you say about brake lights Jason. You’re too involved.
It’s like asking a guy with a boob fetish if some particular representative shape or mass is objectionable. Of course he’ll say no. All of them are good. The world, as it exists, is a palette of joyful variation.
Despite your logical argument, I’m still giving you side eye.
The growing brake lights feel like something that could have mass adoption, they’d be useful in a lot of everyday driving situations.
The problem I have is if you show me screenshots with the brake lights on and with them off, I’m not sure I could tell you which is which. I’m sure I’d figure out eventually while following one, but I can’t think of any other car that I can’t tell just by looking if it’s braking w/o extra knowledge of just how that model implements brakelights
Way better summation than what I was trying to type out. Yeah, they’re clearly two distinct patterns of braking vs. not, but which is which won’t be clear in a given moment for the unfamiliar.
“I can’t think of any other car that I can’t tell just by looking if it’s braking w/o extra knowledge of just how that model implements brakelights”
Well, kinda any pre-1986 American car that has a single pair of red taillights that use 1157 dual-filament bulbs. If it’s just driving with taillights on, you have two red lights in front of you. If the brakes are applied, you have two brighter red lights in front of you. Generally the brightness differential is substantial, but sometimes it ain’t. And sometimes you get some chucklehead riding the brake pedal and defeating the whole purpose of brake lights, but whaddayagonnado.
So, where is the outrage with the Ram’s current brake light design? The brake light (red, of course) goes away completely and converts to amber with NO RED when the turn signal is on? You see a Ram 1500 at a stop light with the right blinker on and there is NO brake light on that side. I know it’s common for a red bulb to change from a brake to a blinking light on many lighting units, but this takes the red away on that side entirely which just seems *odd* to me.
Interesting point, I suppose that does mean that brake lights turning off are legal.
It’s incredibly dumb.
Having outer lights that actually change shape under braking is a god-send. I live near a college town so see a lot of hand-me-down beaters with dead CHMSLs that are driven by kids with no money to fix them, and a marginal difference in brightness of the two outer lights is useless. Not to mention with Tesla build quality being what it is, it’ll be months after launch when the center bar starts frying so you’ll actually be required to rely on the outer two lights for braking while there’s a 6-month parts backorder.
Tail and brake lights have been pretty much standardized in the way they display and operate for many decades. With a few well known exceptions. And we all figured it out.
Turd boy’s design here is fucking Christmas light bullcrap. Society has gotten way too stupid and distracted to expect people to “learn and adapt” to Rocket Boy’s bullshit solution that no one asked for.
Yeah, this truck is gonna rule. /s
Another great thing is all the bros I see in their trucks who install the led light strips under the tail gate. Most of the time the trucks have no working factory tail lights, and the damn chicken shit leds light up on one side only, so it looks like they are planning on turning when tapping the brakes. Wiring must be hard or something…but hey bro, cool truck!
the whole point of the third light is to have a reference light that is OFF when the brakes are not being applied. If someone is not actively looking at the lights when they come on, it will be confusing because the only difference will appear to be that there is LESS area emitting light.
This will be made worse by all of the idiots I see driving around in their Teslas and German luxury cars with their rear fog lights on. Lessens the contrast between off/on.
Actually, I think this might be illegal per this section of the FMVSS:
S5.4Equipment combinations. Two or more lamps, reflective devices, or items of associated equipment may be combined if the requirements for each lamp, reflective device, and item of associated equipment are met, with the following exceptions:
(a) No high-mounted stop lamp shall be combined with any other lamp or reflective device, other than with a cargo lamp.
I’m also not sure on whether being able to drive with the tailgate down could cause it to run afoul of one other: S5.3.2.2If any required lamp or reflective device is obstructed by motor vehicle equipment (e.g., mirrors, snow plows, wrecker booms, backhoes, winches, etc.), and cannot meet requirements of S5.3.2, the vehicle must be equipped with an additional lamp or device of the same type which meet all applicable requirements of this standard, including S5.3.2.
Good find. I also found this that might make the tail lights turning off illegal:
S5.5.10The wiring requirements for lighting equipment in use are:
(a) Turn signal lamps, hazard warning signal lamps, and school bus warning lamps shall be wired to flash;
(b) Headlamps and side marker lamps may be wired to flash for signaling purposes;
(c) A motorcycle headlamp may be wired to allow either its upper beam or its lower beam, but not both, to modulate from a higher intensity to a lower intensity in accordance with section S5.6;
(d) All other lamps shall be wired to be steady-burning.
S5.5.7On each passenger car and motorcycle, and on each multipurpose passenger vehicle, truck, and bus of less than 80 inches overall width:
(a) When the parking lamps are activated, the taillamps, license plate lamps, and side marker lamps shall also be activated; and
(b) When the headlamps are activated in a steady-burning state, the tail lamps, parking lamps, license plate lamps and side marker lamps shall also be activated.
S5.5.4The stop lamps on each vehicle shall be activated upon application of the service brakes. The high-mounted stop lamp on each vehicle shall be activated only upon application of the service brakes.
Of course, I’m not even sure this legally qualifies as a high-mounted stop lamp.
It is legal. The supplier checked the regs months ago and certified.
Just tie a red flag on it and will be fine.
Would be no different than SUV’s with the 3rd brake light in the tailgate window and driving with that up. Or back in the day with hatchbacks.
You’re right that other vehicles likely have the same kind of issue. Which leads one to wonder whether this goes unenforced or has been ruled to specifically apply to additional equipment. It’s also possible that the term “obstructed” specifically applies to something blocking the light, rather than pointing it down or up. I wonder if the companies making tailgate pads need to have cutouts if a pickup has the CHMSL on the tailgate.
It’s really interesting to see how these regulations are interpreted and enforced. As others have pointed out, there are even examples mounted below the brake lights, which seems like it would run afoul of the regs.
Doesn’t apply to CHMSL for trucks on the liftgate as long as the liftgate isn’t removable. Weird but true.
Another issue is that the FMVSS defines a high-mounted stop lamp as “…a lamp mounted high and possibly forward of the tail, stop, and rear turn signal lamps…”
There is potentially some ambiguity in the wording but in practice CHMSLs are, you know, higher than the other stop lamps, taking “mounted high” to go with “of the tail, stop, and rear…” I suppose one could claim that “mounted high” does not go with “of the tail etc.” but then what does “mounted high” actually mean? Can a CHMSL be the same height as the other brake lights if they are also “mounted high” and, if so, is that really a good idea in terms of distinctiveness?
I think that the assumed interpretation must be correct on account of the word “mounted” having to apply to both “high” and “possibly forward”
I agree this is both the more sensible and the grammatically sounder interpretation. I can still easily imagine someone getting paid to argue the other way, though, taking the construction to mean “mounted high” and “mounted possibly forward of…”
It is more complicated than that.
Not always.
https://upload.wikimedia.org/wikipedia/commons/thumb/3/3d/1996_Chevrolet_Lumina_APV_Sport_%28rear%29.jpg/2489px-1996_Chevrolet_Lumina_APV_Sport_%28rear%29.jpg
Fair enough. I wonder whether that required a waiver?
Not sure. There are other examples I can think of which aren’t as extreme. This generation Dodge Daytona had the CHMSL in the panel between the reverse lights, so the same height as the standard brake lights.
https://ik.imagekit.io/vfrk1urj3wi/JpegImages/OldImages/AR0803x-p17-200.png?tr=w-1200
Waivers are not allowed but this lamp is legal so no need.
They can be mounted anywhere for SUVs and trucks. The mounting height requirement relative to the glass ( max 74mm below the glass) is for cars.
It isn’t combined with the tail light. When you watch the video you can see that the CHMSL is mounted below the tail. It is legal. Source: I am an optical engineer at an automotive lighting company that is a supplier to Tesla.
Looking at both videos again, it looks like the CT’s lights meet this off/on requirement, at least technically. The non-breaking tail lights are the highest strip of LEDs across the whole rear. When the brakes are applied, the CHMSL is in a different row of LEDs, so technically, the CHMSL light was off and turned on with breaking. Granted, the reality is that fewer overall LEDs appear to be lit during braking, but they do appear to be higher intensity. Whether the contrast is adequate for real driving situations is certainly debatable, but it does appear that Tesla meets the letter of the law in regards to on/off operation.
I’m not convinced. I think at the very least it reuses the top row of lights, but I think it only appears thicker because it’s brighter.
It doesn’t use the tail LEDs. You are incorrect. Source: I am an optical engineer at an automotive lighting supplier that makes lamps for Tesla.
Interesting. I rewatched the second video and can see that now. It seems like it follows the letter of the law but not the spirit of the law.
Excellent observation. You are correct.
Clearly they are not perfect especially by Tesla standards. They are not allowing the owner to customize light patterns and functionality. Haven’t you seen the Volvo commercial with the Mom trying to pick the perfect headlight functionality?
If I remember laws right, it likely won’t be exported to Europe because it’s so big and heavy it would require a commercial license.
EU driving regulations states that the most popular B class licence is valid for vehicles up to 3,5 tons/3500 kg (and carrying not more than 8 passengers). I don’t know if official specs of this monstrosity have been published, but according to Munro, Cybertruck should weigh between 6800 and 7000 punds, which is ca. 3100 kg. So theoretically below the limit. Still, I don’t think it will meet homologation requirements (pedestrian safety, dimensions, proper lighting etc).
The F150 Lightning is limited to 50 mph in Finland.
/rolls grenade into comments section/
C’mon, Jason. No one really cares about taillights.
The whole article was an incitement of the comment section. And I’m here for the low stakes :).
/throws self on grenade. flashing amber. bright red glow. low red pulse/