GOOD NEWS, EVERYONE! Consumer reports picked up on this video and did testing which confirmed that this issue affects nearly all Hyundai/Kia E-GMP platform cars (and I very much appreciate them giving a shoutout to this video!) https://www.consumerreports.org/cars/car-safety/brake-lights-can-fail-to-provide-fair-warning-on-some-evs-a9533519285/ And now! Hyundai will fix this. They're calling it a "field service campaign" and it will begin in July. Weirdly, Kia hasn't said anything yet at the time of this comment's posting. https://www.autoblog.com/2023/06/15/kia-hyundai-genesis-one-pedal-braking/ Now, while I'm glad Hyundai is doing the right thing (and hopefully Kia does soon), I believe we still very much need a clear, unambiguous regulation to unify brake light behavior with features like one-pedal driving. We are still leaving too much up to manufacturers right now.

LET'S GOOOOO! 🎉🎉

Great news - thanks for debugging the laws! ❤🖖

nice work

Could you do a video highlighting the car's charging issues next? There's widespread issues with Level 2 charging on the Ioniq 5 when charging at higher amperages (typically over 32 amps). The service campaign they released to address the issue simply throttles charging down to unacceptably low speeds. Doesn't seem like Hyundai cares enough to issue a recall.

"Field Service Campaign" Is that what we're calling "recalls" now? 😂

As a software engineer I feel qualified to say that one man's software can also be the same man's nightmare.

Agreed 😂

nightmware

"can also" ? as someone who's almost two decades doing this. software IS nightmare.

​@tsartomatonighware

I feel called out.

An old friend of mine developed a progressive brake light as a uni project back in the late 90s/early 2000s. Gentle brakes had one light, full brakes were 3 lights. At the time it was deemed "too confusing" despite the fact I feel like it should be a requirement these days.

Most cars do similar but different manner: in the event of a sudden hard brake, either flashing the brake lights, or hazard lights activate.

It would have no real impact these days but sure at it to the ever increasing regulations list that has caused cars to become the bloated monsters they are today

@michaelkeha Regulations that make it safer than ever for you, your family and everyone else sharing the roads. They save lives. You should be thankful as there was no safer time to crash than today.

@allastor actually many regulations run contra to safety as they have to compromise to fulfill other regulations like environmental ones and keep in mind all of this is added to what you have to pay for a car while making people more likely to take risks they didn't before due to that increased safety

@michaelkeha Actually, all I read was excuses and not a single trusted source. So you said nothing.

I was a witness to the other extreme. There was an electric car in front of me on the highway and its brake lights were continuously going on and off like a Christmas tree. It was incredibly confusing and annoying, especially give the fact that the car was going at more or less a constant speed. I was very happy to take the opportunity of passing it asap.

This is hilarious 😂

Like at 21:30?

yes, especially with super bright instant LED lights

I wasn’t in the mood for a discussion about death today so Hank Green led me here. Really informative video!! I can now say I know a ton more about car lights than I ever thought I would.

I was so excited to see Hank link to this video! I have a hybrid and I never even thought to check what the brake lights were doing, hope some US regulation comes soon!

Thats awesome, i was happy to see him give the shoutout. They both have shouted out each other in the past, so cool to see. Both channels have been a blessing over the past few years

Same here

Did he tweet about it or something? I ended up here out of interest but kind of wished I caught it with the rest of the club lol

@Dustin It was in a vlog around a week and a half ago! He put it in the description

Congratulations!! You started to discuss the issue and now it's being fixed. Great job and I'm happy the OEMs are paying attention, one way or another.

When Hank said "electric car brake lights", I thought to myself that I'd be sorely disappointed if it wasn't Alec's video. I am pleased to have the reminder to watch it again.

I saw this video when it came out, but it made me really happy to see hank shout it out! This channel deserves some love

I immediately thought of this video, and after clicking the link after watching his video, I realised I never finished this one, as it threw me right in the middle 😅

I immediately thought of this video too, I'm glad Hank didn't disappoint us

Same!

I’m an automotive lighting, safety engineer, and just shared this with my team. Keep up the good work 😇

If you're at one of the manufacturers that does this, could you ask the team to stop doing the thing where brakelights FLASH every time you press the brake? It bothers me when I see it, because flashing your brakes already means "back off," and sending that message every time you brake is like leaning on your horn every time you have the car in gear; it just leads to alert fatigue and reduces your ability to actually communicate with the drivers around you.

@SirBlastalot in DFW area in Texas a lot of the dealers do an aftermarket device that flashes the brake lights.

@SirBlastalot I think this happens for safety reasons, a lot more noticeable that someone is braking at night, though i'm not entirely sure how true that may be

Also turning on reverse (white) lights when unlocking a car needs to stop. This makes it appear as if a car is about to back up, but it's just being unlocked in a dark environment. It adds alert fatigue which means when someone really is backing up, you might think they're just getting in the cars. I think Chevrolet does this and it drives me nuts.

@SirBlastalot its a safety feature so you have no excuse but to notice them braking. in motorcycle academies they advise you to, albeit manually, flash the brakes before fully braking so you can be seen. your sadly a minority

I've been behind several hoopties with no brake lights, whether broken or intended insurance fraud. It's absolutely terrifying in the moment you realize they're slowing.

It's worse when the brake lights are permanently ON, as they're blinding

​@MISC BITSseen a couple with reverse lights on at all times or broken rear housing. Feels like a flashbang is driving in front of you. Also it absolutely baffles me how many people dont want to spend 20 bucks for a new headlight and instead drove around with a single one. Or maybe they dont even notice, thatd be even worse.

The same issue exists for non-electric cars and motorcycles though. I often slow down my car or motorcycle by downshifting and releasing the clutch. It can result in significant deceleration without the break lights being activated. In fact, I often use this methods to bring my car/motorcycle to a near stop.

On a bike, you should at least tap or drag the brake before and whilst slowing. It's not like you have to move a hand or foot to reach it and your safety is on you. Especially when it's a problem you know and are in control of.

Brakes are there for a reason - to slow you down. Brake lights are there for a completely different reason - so people behind don't run into you when you brake. Using the engine to slow you down is simply not as safe as braking 'properly' (and yes, I do it, like everyone else). The EV situation just makes everything worse.

I work with trucks for a living, and I've been thinking and talking about your two color break and turn video since it came out. Thank you for giving me something new to advocate for!

Thank you for doing your part to make our world better…and safer. I appreciate you.

Hank Green: "There's a chance I might die of cancer despite everything I do. Also Hank Green: "Hey you wanna watch a video about brake lights?"

Where did he mention this?

Got my "optional recall" update done today. Got the notice in the mail a few weeks ago. Pretty sure you are solely responsible for getting the ball rolling on this, and thank you so much for that.

No matter how uninterested I think I am in one of your video topics, you manage to prove me wrong every time. You never cease to make those topics exceedingly interesting. Thanks for that.

Is it bad that when Hank said "I'm going to link you to a video about car breaklights" I knew that I'd be ending up here? ❤

Why would that ever be a bad thing?

who else would make a video about some weird niche thing like electric car break-lights other than alec

*Brakelights

Thank you for doing this video and spurring the subsequent action. This is something close to my mind as a professional driver. The older transit buses I used to drive did activate brake lights when the electric transmission retarder activated when the throttle pedal was fully let up, plus the normal requisite light activation that goes along with the service brake (see, used to that industry term - it’s specific jargon in air brake world) application sending air pressure to the brake chambers (note: not a pedal switch; air brakes typically use a pressure switch in the air lines, which I also mildly disagree with). The hybrid buses I drove also activated brake lights any time the throttle pedal was fully let up, which activated both regen AND a transmission retarder. My current vehicle bothers me though. Now I drive a newer IC school bus that has an exhaust brake operated by the variable geometry turbocharger vanes on my Cummins diesel - it has an on/off switch on the dash. I use the EXH brake every day when I descend a long hill on my route, but I think I’m the only driver who’s schooled in its existence. The brake lights are NOT activated when the throttle is fully let up and the EXH brake activates. It provides pretty remarkable deceleration at higher speeds because it also throws the computer into a “slow down” mode wherein the transmission automatically downshifts at higher RPM to aid in decel. I find it dangerous. The ONLY brake light activation on this newer bus is the aforementioned air pressure switch in the service brake air circuit (so a service brake pedal application). Another tricky note I think you’d appreciate, Alec: When we lose air pressure in our air tanks, the “emergency brake” automatically applies (when tanks are depleted to between 20-60psi by law) - it’s the same spring brake application as the bus’ parking brake, just a well-designed fail-safe application process (which we test daily). The spring brake application, whether it’s being used as the parking brake OR in its emergency application mode, does NOT activate brake lights. So if I blow an air line on the highway and lose all my air pressure, the spring brakes will set automatically and bring the bus to a gentle, controlled stop, but WITHOUT any brake lights. It bugs me too.

The bloopers are a great addition. I always appreciate when people are willing to show they are not perfect even when they are teaching you something. It is something we should see more of. It is a great trait to be able to see fault in yourself but not let it stop you from growing!

How this guy gets me and 2 million other people to watch a 29 min video about "another brake light problem" is pure magic. 🧙

Because this is Technology Connections, I love his videos to!

Bro I'm thinking the exact same thing lmao

TBF, I'd watch the sequel to this 😅

Petty complaining unifies "people"

being surprised about learning things is strange honestly

It makes me so happy to see you put as much (or more?) thought into this as I have been for the last several years! Have you done a video about Tesla's problem with this? Tesla has nailed so many small details in their cars, but their brake lights are TERRIBLE! When slowing to a near complete stop with regenerative braking, the brake lights start on and then go off when the car slows down (maybe the same as GM). This is very dangerous in many situations and needs to be changed!!

This is incredible!! I can’t imagine following a car like this on a high speed roadway and not seeing brake lights. Shocked this is allowed to EVER happen and kudos to you for actually finding this issue! Has it been reported? Idiotic flaw… incredible!

Lol you never been behind a car without working brake lights?

Or a car/motercycle down shifting has this same problem. This isn't a new or specific to ev problem at all. The solution of decel lights could be applied to all of these.

THIS. I've driven (and ridden behind) an Ionic, and the lack of break lights when auto-breaking is the scariest thing for me. I'll touch the break petal (even if it jerks the car a bit, b/c those breaks are STRONG) just to warn the person behind me that I'm letting my foot off the gas. P.S. Hank sent me here.

Did you break your car, or did you brake your car?

Break = opposite of fix Brake = slow down

For us to easily visualise how aggressively the car is slowing down, perhaps it would have been a good idea to do a similar deceleration with a normal petrol car (either at the same time or one after another). We'll be able to easily see whether a brake light is needed to warn us.

I was hoping that Hank's link to an electric car brake video was this video. It's a great video and everyone should watch this.

Same!

“May I remind you, I was able to stop my car from 60 miles per hour or 96 and a half kilometers per hour in 13 seconds or 13 seconds” This made my day 😂

As a certified horologist myself, I can confirm that 13 seconds is in fact equivalent to 13 seconds.

They may both sound like seconds but only one is FREEDOM SECONDS

@Night Kobun Those damned seconds conversions, a real thinker, that one.

Thank god metric time never became a thing!

😂

Love your videos and your satire. I have a pet peeve with back-up lights being used as general illumination. Especially since my area has a bunch of on street angled parking. If you don’t catch them walking next to their car, you think someone is backing and just released their brake.

I've been suspicious this has been the case with my EV6, so I sometimes tap the brake just to be sure. Always good to reinforce that one of my paranoias has been justified

From cancer survival rates to electric car brake lights, today's been a wild day on youtube. New genre unlocked.

Fuck I'm sick of reading comments about that guy

​@William Campbellhehe "sick" nice one

Great post, thank you! I like the GM accelerometer solution because it addresses the issue I have had with manual shift cars for years (before any type of electric car was even a thought) - the brake lights don't turn on when someone is downshifting instead of braking to intent to stop. It's a simple solution that addresses all reasons that a car could decelerate.

They should use accelerometer as additional data source to turn on the stopping lights

This man has more passion for car signals than most people have for their marriages. Truly the hero we needed but dont deserve

Marriage is overrated anyway

And heat pumps.

@Alexander Robins Well heatpump is everywhere, it is foundational. That's how the universe works otherwise everything just stops.

I don't see a ring on his finger, so I don't think he has enough brainspace or passion left over for much else.

Based. The 88th like is yours you diserved it.

Excellent video discussing the braking light concern in these vehicle models! Nevertheless, it's important to emphasize that Hyundai and Kia are grappling with an alarming surge in vehicle thefts. Their response to this matter seems somewhat laid-back, recommending a visit to the local police department for a steering wheel bar. Such a security vulnerability raises substantial apprehensions for potential buyers like me, and it's vital for manufacturers to address these matters seriously to ensure customer safety and confidence. When combined with the brake light issue, this budget car's value comes into question. 😬

Very informative. I would also like to point out that manual transmission cars also decelerate relatively quickly upon releasing the gas pedal -- especially if they have a high compression engine and are using a lower gear to decelerate. There are times where my breaks are engaged only just before I come to a complete stop. So.. A manual transmission car has the same problem as the i-Pedal mode of your EV, except that mine does not engage the break lights if I release the gas pedal completely. It only engages the break lights once I hit the break pedal. Back in the dark ages when I took my driver's exam, one of the questions on the test actually brought up this exact situation. I don't remember the specifics of the question at this point, but it basically asked if there were situations where a car may be decelerating quickly without illuminating break lights. As this was back in the dark ages, the answer was not multiple choice but instead provided enough room to write a short essay.

I thought this was going to be an interesting video on a problem I don't have to worry about...until you mentioned adaptive braking. I use adaptive cruise control all the time.

I was just in traffic the other day, behind one of these Ioniq5 cars. Luckily we were in an area I was very familiar with and so I knew to brake but I noticed his brake lights appeared to be burned as we slowed down, eventually they turned on, and I was wondering why that was. Thank you for the explanation, I was clueless that automotive engineers would really let such a flaw go unnoticed, its almost like it just feeds into the whole controlled obsolescence thing, probably gonna be the cause of a few accidents here and there in the near future.

Views are probably gonna spike weird on this. Last Vlog brothers video said they had a link to a vid about electric car brake lights and I was like "Technology connections" and I wasn't wrong. Having said that, 2.4 million views is pretty nice already.

yeah my first guess was technology connections and i was like "oh right i havent watched that one yet~! thanks hank!"

When he said it was a really interesting video about electric car brake lights, I immediately thought of this. I'm happy to see lots of new people possibly getting hooked on this channel.

"The brake pedal was the only thing that can slow down the car enough to warrant turning on the brake light" My mangled standard transmission would like a word with you

I guess he has never driven a manual transmission in anything and never heard of engine breaking.

Unless its a diesel with an engine brake you are not getting that much engine braking to warrant the brake light

@Luc Greco I’d like to see where the line is drawn, though.

@Bill Z "Engine breaking" is a good way of putting it if you over-rely on it. Engine braking is a useful technique, but it should only be used for moderate speed control, like going down shallow slopes or gradual reduction on a motorway. If you're using engine braking such that it warrants a brake light to come on, you're wearing out your gearbox - brake pads are cheap compared to a new gearbox.

@ValleysOfRain Correct sentiment, but it's the clutch disc which is going to wear rapidly instead of wrecking the gearbox by using downshifting as a service brake.

Really glad you've done a video on this. I was just the other day wondering about braking with electric cars and brake lights due to the regenerative braking. I'm not even joking.

Wonderful video as always, but I feel compelled to suggest that, as EVs become more widespread, the time has come to use the correct term for the 'gas pedal', namely 'accelerator'. 😉

My very first car was a DAF 66, which did engine brake when you took your foot from the accelerater. I was rear ended by a police cruiser when I slowed down for a red traffic light. Miraculously the brake light still worked when I depressed the pedal.

Thanks for warning us that there are cars with this behavior. I've definitely driven behind Teslas and noticed that I need to pay attention to their deceleration more as they can decelerate faster without the brake lights coming on. But having them not coming on at all is far worse, especially in traffic that can create random unexpected stops after seemingly smooth cruising.

I've thought before that a good feature would be lights at both sides of the car that indicate acceleration/deceleration with coloured lights, the redder the light the stronger the deceleration, orange/yellow lights at steady speed, and green lights to show acceleration

This is a common issue with motorcycles. Because engine braking is so strong, you use your engine for 90% of braking. You learn a habit of tapping the brakes if there is someone behind you just so they are aware.

Motorcyclists usually know this (or they aren't motorcyclists for long) but your average Midwest housewife with the Ioniq or whatever this car is, isn't going to know that.

@Benevolent I have to admit that I do not practice this as frequently as I should. Tapping the brakes messes with my ability to downshift quickly, but staying alive is more important.

sounds like they need an accelerometer brakelight

Or even manual cars.

Yeah I used to do that when downshifting aggressively with my civic

Thank you for this video! I was a very nervous Bolt owner for the first 13 minutes of this video. I'll be sure to hit the actual brake from now on when coming to a full stop just to make sure people know I'm completely stopped

I think what you need to do in the interim is do you fancy one-pedal driving with your right foot, and when you're slowing down quickly, use your other foot to hit your brake light indicator pedal

I’ve said this for a while, and fully believe it. All cars should have red/yellow/white lights on the back. Red for braking and to see that a car is there, yellow for turn signals because it sticks out more, bright white for backing up because it can help people see that a car is backing up before they see the car if it’s around a turn or deep in a parking space

Great video. Like yourself I can’t believe this was even necessary. Thankfully you seem to have had a very positive impact on the industry already.

THANK YOU for bringing this to the attention of those who can do something to remedy a ridiculous situation. KUDOS ! ! !

I am glad he added the metric seconds, I hate when the US content creators only use imperial seconds.

We don't use imperial seconds, we use customary seconds.

metric users when there are 60 seconds in a minute instead of 100

@Ashton Howard Sorry, come again? I only understand metric English.

Should we insist on non US creators using metric time as it was intended. With each hour consisting of 100 metric minutes, and each metric minute consisting of 100 metric seconds.

Pretty sure it's sloppy seconds

I used to kinda hate the look, but the way you compared the braking with a smooth elevator is making me want one now lol

You might also want to consider manual transmission using engine breaking to slow down, as I can slow down fairly sharply by downshifting, all without application of the break pedal. This could be considered a problem.

Thank you for bringing me here Hank, this was absolutely fascinating. Great content here

Don't worry brother, I spend a HUGE portion of my day contemplating DRLs. I feel you.

My guess as to why it has never been associated with rate of deceleration is… remember when we had manual cars? Downshifting can provide quite a bit of deceleration without brake lights. So technically an EV or Hybrid slowing down pretty much with the same intensity as an aggressive down shift, is basically the same thing. When I had my 5 speed manual accord downshifting was a great way to slow down when you notice a cop pulled out from a side street and I was going a little too fast. No brake lights and you could takeoff speed. I’ve not checked to see yet on my current car (2023 CRV sport touring hybrid) if pulling the “parking brake” which when moving just applies the service brakes at maximum and also engages the abs, but should that system fail, it then applies the parking brake servos to clamp the rear wheels, but I don’t know if the brake lights are activated during this event. But you’ve got me curious now.

I love how your videos range from "I'm really bothered by this very small design issue in this very specific product" to "Many people may die because engineers are lazy"

I could be totally wrong and this could be unwarranted but it definitely looks like you've been working out man. Looking amazing. Keep that s*** up 👍

It’s not that engineers are lazy. It’s that manufactures are cheap. They can save an extra bulb and wiring. Easy money. As far as the software bmw already had this software designed into there cruise control. If it was slowing itself down it would illuminate the brakes if you were slowing down faster than some meters per second rate. This was back in 2008 as that’s what’s in my cars owners manual. People always say the Germans over engineer but they seem to actually think about the important things like brake lights. They also have a multi state brake light system so if your stomping on the brakes it illuminates a second set of lightbulbs, giving you more advanced notice as the driver behind them. They also flash your third brake light when you slam on your brakes and activate ABS. This multi stage braking system should be standard across the board for all manufactures.

@FishFind3000 It's not that manufacturers are cheap. It's that upper management needs their $100k yearly bonus. They can charge customers the same amount and undercut production cost. Easy money.

Sometimes there's a fine line between the two. Sometimes not even that.

​@TaleDreamer prioritizing profits over safety, as usual.

As an existing subscriber to the channel and blog brothers, I’m so glad to see an unofficial collaboration!

I appreciate you making such an amazing case for the internal combustion engine.

I finally got to drive an adaptive cruise vehicle and the first thing I wondered was whether the brake light was activating... ~Trav

Another issue with the brake lights on these cars is when using the cruise control. It’s been discovered that every time the car goes down even a slight downgrade, it constantly illuminates the brake lights even though you are still running at a constant speed. Let’s hope their software update deals with this flaw as well.

I was pleasently surprised to see that Hank suggested this video. Cool that he knows and like this channel as well :)

The most shocking thing in this whole video is the fact that GM made some good decisions.

I mean, every so often they do. Though they usually seem to screw it up anyway.

Whichever engineer did it was probably canned that year or the next.

A broken clock is right twice a day.

GM has a pretty damn good engineering team, it’s the rest of the management that makes them unreliable

And they solved the PRNDL/brake light problems too!

I think using an accelerometer is a genius idea, MEMS-type accelerometers are extremely accurate and reliable so they're using physics to determine the brake light state which will be accurate under all circumstances, opposed to a software-based implementation which can have bugs and is much more complicated to implement properly and safely.

I have an electric car from 1998, it is a Solectria Force (built off of a Chevy Metro chassis) and this car has a calibration parameter in the motor controller for how much regen torque should result in brake light illumination. The early EV conversions didn't mix pedals with fancy brake blending so they put a bunch of regen into the accelerator pedal which allows the one pedal driving you refer to. So, I was always happy with the brake light trigger point when driving this car... until, I finally updated it from lead acid batteries to lithium ion, with the drastically reduced weight, the car would decelerate quickly without illuminating the brake light. I found an old PC laptop, loaded up the windows 98 app for RS485 telnet and calibration, adjusted the setting, and was good again. I cut the current/torque setting in half, and it was perfect.

Thank you for bringing this up. What do we have to do to get the update to fix this issue?

Wow this was/is a very useful video to put out, thank you! Not too many folks here in my particular neck of the woods actually have an EV vehicle yet, that I've seen....BUT knowing what I do now, I'm not gonna be following one unless it's a good safe distance ahead...😊

I think what we need to do is try to build cars as simplistically as possible. The problem with making things "more advanced" Is they become infinitely complicated which causes infinite amounts of failure points. Take a door for example A normal door has three hinges. If the door stops working it's more than likely those three hinges. Now if you have an electric door on the track with a motor there are multiple areas where there could be problems. The track could be misaligned The door could have got warped so it doesn't fit within the track There might be an issue with the motor There might be a power supply issue There might be a wiring issue We need to make cars like basic doors. As simplistically with as few failure points as possible.

After I had watched this video last night, I decided to talk about this video with my coworker that I was driving with. After explaining it we were stopped at a red light behind a couple cars and THAT EXACT CAR PULLED UP IN THE LANE NEXT TO ME AND FLAWLESSLEY DEMONSTRATED THE ISSUE WITH THE BRAKES. I love when things like this happen directly after learning about them

Thanks Hank green

"When you depress the brake pedal." I felt that one.

My new Accord hybrid is pretty good about using the brakes lights in either decel conditions using the paddles (light decel, no brake light, any level that appreciably slows the car get the brake light), or in auto-cruise--same deal, if it slows more than a touch, the light come on. I've been pretty impressed how good that system is.

I dealt with this issue with a Tesla Model 3 or S in front of me. I couldn’t tell it was slowing down until I got quite closer all of a sudden. It happened a couple times with a close call until I switched lanes.

They could design a row of Led's for the brake light along the trunk lid or the rear roof line that would illuminate along its length from right to left slower and shorter or faster and longer similar to a bar graph VU meter and it would operate on deceleration with the input from an accelerometer type of sensor. The driver behind you needs to know when and how fast you are stopping or slowing down and we have the technology to do this. Good video!

as an italian who spent 6 months in america, i got to new york and i was like what the hell is that beeping red light on the side? then someone explained how it was the turning signal and it was just very shocking to me. I mean throughout the six months I was still confused sometimes, especially in bad weather, to understand if someone wanted to turn or their brake lights were malfunctioning or something.

I love the engineers who decided to separate the rear turn signal light, and put them below the bumper, where you can see it from a distance ahead of you, but not when the vehicle is next to you, or in front of you.

I think this is Hyundai or Kia that has done this on recent models, Sportage? I don't like it, they are too far apart. I prefer all the lights to be at one level, so I don't have to glance up and down the rear of the car to know it's intentions. Plus I think they are just like what Alex complains about and I agree with, they are all red in color, not amber etc.

I see these in Aus frequently and it's absurd. We're all used to turn signals being somewhere in the middle of the cars height, about waist height, with all the other lights. And it's been like that on every car since the dawn of time. Suddenly on this car the indicators are at knee height instead and you're seeing their brake lights come on up high and it takes a second or two to realise there's an indicator down near the ground that blinking. So utterly dumb

Yes, I agree that the HYU/KIA vehicles that have their brake and turn signals Below the Bumper Covers NEED to have them recalled Immediately and wired such that the lights that are above the bumper cover are used, the Traditional Location for many reasons.

If you can't see the bumper it's considered tailgating in France but you're right too

I believe this has to do with the car's back door. In Europe,turn signals must be visible at all times whether the back door is open or closed. Which means that if the door opens sideways, you can't have the indicators right next to them. You want the hazard lights to be completely visible when your car is standing at the hard shoulder of the motorway, even while you are grabbing the spare wheel from the (open) trunk. As a result, the European versions of quite a few cars have their turn signals (and tail lights) moved below the door, and only the brake lights where their American counterparts would also have the turn signals and the tail lights.

The brake lights being on when stopped being a desired functionality is interesting. In the UK that's actually a violation of the highway code as you should not be using the brake in an extended pause in driving (so as not to dazzle the driver behind). But then we have different coloured indicators too XD

I totally agree with you but could something similar be duplicated with a gas car by downshifting aggressively and using engine braking?

Yes, if you have a combustion engine in a car or have ACC it does that automatically based on the position of the valves and the mechanical resistance in basically every moving part of the engine modern cars just do it better since the clearances are tighter and computers control the whole thing.

Maye the conclusion could be a simple gyroscopic accelerometer that illuminates the brake lights when it detects deceleration greater than a predetermined cutoff value. This could be a simple all-in-one solution that may not require software, and would cover any situation the car might slow down in. Edit: I see from later in your video this is what GM did with the Bolt.

I have thought about this many times before. The brake lights should illuminate upon rapidly slowing down by any means. It has been an issue since before the rising popularity of electric vehicles. Motorcycles have a tremendous amount of engine braking power, able to rapidly slow the bike down without ever touching the brakes; that goes for combustion engine motorcycles. It is a serious topic when it comes to electric vehicles because the regenerative braking can be a lot more powerful. What I fear most is that it will go unaddressed by most manufacturers and then once electric motorcycles become more mainstream, their regenerative braking will slow them down faster than ever before but with no warning to people behind them. I fear it will result in a lot of motorcyclists being rear ended.

As usual, GREAT critique, my friend! And I know this may be slightly off topic, but if anyone is going to get hot under the collar about this DANGEROUS fail, I know you will. It's the function you mention in this review -- the Auto Assist Cruse Control. I have this on my 2018 Honda Civic and I understand that it is a now a common function on most all cars since the last 10 years. When engaged, it will allow the car to cruse at a speed that you set, but it will also sense the speed of the car in front of you and it will adjust your car's speed to that car all the way down to a full stop should that car stop. It will also sense if an object of any kind moves into your car's path. That all works just fine...until it doesn't. No question It is quite an advantage, especially when you are driving in bumper-to-bumper traffic for long periods of time. It takes the stress out of having to focus intently on what the car in front of you is doing - BUT here's a VERY SERIOUS FLAW, much more of a potential hazard that your break light issue. In my Civic, I can be driving along for a long time, just for laughs, let's say an hour with the AACC engaged. The car has been faithfully watching the car in front of me and slowing down when it slows down, stopping when it stops and going again when it starts to move again. I am lured into total confidence that my car will stop when necessary and it will...IF, that is, I didn't inadvertently step on the brake, even for an instant, during that hour because if you even just tap that brake peddle for a second, the AACC will disengage completely and your car will NO LONGER follow the car in front to a full stop, au contraire mon fraire, it WONT STOP; it will just keep on cruising...RIGHT INTO the car in front of you! So how come I don't realize the Auto Assist Cruise Control is OFF? Well be cause the Honda engineers did not give me any substantial indication that the AACC has turned off. I am still driving oblivious to that changed condition, thinking it is still on and protecting me from a collision. TERRIBLE HUMAN INTERFACE -- The indicator for the AACC function is a small little icon in the upper right hand corner of the dash. When it is ON, that minuscule icon shows a small number, like say 55, meaning the cruse control speed is set at 55mph and it will keep the car moving at 55 miles per hour unless a car in front of it slows down. When you stip on the brake and the AACC turns off, the only indicaton that that has happened, is the 55 changes to OFF. And get this -- the position of the AACC icon not only is very small, it is placed where t can easily be totally obscured by the steering wheel, depending on your height. And even if you do see it, it is so easy not be aware that it has changed and is indicating that your car now wants to keep driving at whatever speed it's going at and it WON'T STOP no matter if that car in front of you has come to a total stop, YOUR car will plow right into its rear. I contend that if a mechanism that will prevent my car from crashing into anything in front of it be switched from ON to OFF, there should be some indication should be happening that is obvious and insistent and demanding and a lot more dramatic than a little 10 point text in the corner of the dash changing from 55 to OFF. I say , the whole damn dash should flash red and a loud audible alert should sound to let me know that I now have control of the car and I better pay attention and brake when necessary, because my car isn't going to do it for me! I have spoken to friends who own both American cars and imports and they all have this same flaw -- the feedback to the driver that the AACC has switched off is almost non-existent, and THAT, I must say, is potentially even more dangerous than brake lights not functioning as expected. And putting potential injury aside, even from a fault issue, a brake light fail on a Ecar will cause the car behind you to possibly crash into you -- THEIR fault; the AACC fail on any car and YOU will crash into the car in front of you -- YOUR fault. And here's the thing, the Honda designers already are aware of what to do to get the driver's attention on this kind of auto functionally; for example, the Lane Assist function -- when that function is turned ON, allowing the car's sensors to keep the car centered in the lane, if you take your hands off the wheel for more than 10 seconds, a big yellow bar flashes across the FULL dash with the words in bold 34 point text: DRIVING REQUIRED, plus a loud rapid beeping sound. The SAME thing should happen if you just tap the brake while driving with AACC engaged -- that same level of warning feedback should happen to let you know, you've just set your car to hurl itself into anything that's in front at whatever speed you've set it to "cruise" at. I'm just sayin...

This is something experienced motorcycle riders have been aware of for years. Many bikes have aggressive engine braking, so much so it could easily cause a collision. Wise riders will engage a touch of rear brake just enough to engage the switch, especially when someone is following closely behind.

I do this when I downshift in my car as well, as I noticed that people tended to tailgate me a lot due to the engine braking actually being a thing. So you just get into the habit of tapping the brakes enough to activate the lights but not engage whenever you downshift. They see oh - muscle car - it behaves a little differently but still predictable - must be driving manual.

Some clever bods have recognised this and one can now get inertia switches that tie into the brake light, so that when on trailing throttle, the sensor is activated by the g forces and lights up the brake light automatically,=. I'm thinking of getting one; sounds like a good idea. Not sure of where, just yet.

@Steve Slaughter I could see this being quite helpful on smaller bikes as they tend to suffer from this more due to lower weight and more gears ( as a rule ).

our last MC was a 1973 Suzuki GT380 -- not a lot of engine braking with a 2-stroke ;-)

I was thinking the same thing watching this.

We’ve had a solution for this for years in the motorcycle community because our sportbikes have insane engine braking capability. Especially as you get into bigger and bigger engines. They basically use the bikes gyroscope to determine whether or not to flash the brakes. And the sensors don’t display a hard brake light, it’s a flashing brake light on deceleration with engine braking. It’s a aftermarket mod sure. But a great one nonetheless and affordable.

As a software engineer, I have so little trust for software based ANYTHING when it comes to operating a car. I am perfectly happy in my car that's almost 20 years old, thank you. ❤

The idea of not turning on the brake lights under light deceleration is to avoid the accordion effect in traffic. I dont think the lights not coming on under light braking is fine (because sometimes you can cost and brake just to keep a constant speed for a short moment). But it should engage the brake lights for the duration of the braking if its dragging the brakes for more than a couple seconds.

I used to have a 2006 Lexus GS hybrid with adaptive cruise control and as far as I remember it turned on the brake lights during ACC operation when it was slowing down beyond letting the car coast. I was quite surprised one night when I looked into my rear view mirror and discovered that. While I'm not sure if the car was applying the friction brakes to slow down or slowing down using regenerative braking, it could have been that the signal to activate the lights came from the ABS computer with some sort of fluid pressure threshold or something. But since the hybrid model a completely different braking system than a conventional one due to the lack of a vacuum source in EV mode, why not decelerate using our old friend the electric motor. It might also be, that my car wasn't subject to US-regulations, since I'm german and we have the Straßenverkehrszulassungsordnung ( Come on, I couldn´t not sneak a ridiculously long german word in here) to regulate our cars around here and these cars behave differently in your neck of the woods.

I first drove a Prius in 2005. It has an engine brake mode, which does not activate the brake lights. Even then I thought about the people behind me getting surprised by my slowing without brake lights coming on. And today with the more sophisticated technology, the situation is more complex.

As a truck driver I appreciate bringing up these nuances. As we need more time to stop and anticipate what's the driver in front thinking of doing, or usually not even thinking about it, it's very hard to see at a great distance. When you actually notice the car is showing down without the brake lights you are getting dangerously close.

As a truck driver, do you think the brake light should come on when the exhaust brake alone is in action?

​@Yin Leung good question. definitely not with a full load.

As a fellow truck driver Ive been aware of this problem, but in trucks, not cars. Alot of trucks can change the operation of the jakes based on the position of the cruise control switch and if your using your jakes in throttle release mode, depending on the gear your in, you can be decelerating just as fast or faster than an EV without illuminating your brake lights. I personally only use that mode to maintain speed on a hill and all other scenarios have it set to activate when i touch the brakes so that people know im slowing down

@Yin Leung As someone whomst also has operated trucks, I would say that it depends on how strong the exhaust brake is. If it actually slows you down considerably like the regenerative braking or transmission retarders on heavy off highway equipment I would say yes, otherwise if it merely prevents further acceleration to higher speeds than I would say no.

This. ⭐️

I don't have an electric car, and the regenerative breaking seems to be a tad stronger than the motor brake of regular car (unless you put in really low gear in relation to your current speed) but motor breaking makes up for probably 70% of when I need to slow down during my daily commute... you'll also never see any brake lights.

I am of the opinion that both brake light and turn signals should be RED, but in separate light fixtures. The reason being is that amber turn signals can be nearly impossible to see under direct sunlight. As a kid, I never had any idea whether someone was signalling or not, as I would usually go for walks on sunny days. If there are separate fixtures, drivers behind you can easily discern the different between the brake light and the turn signals, even when the 4 way flashers are being used while braking.

Love the one-pedal driving in our Leaf. I had been interested in the Ariya, but found out that Nissan watered down the Ariya's e-Pedal such that it is no longer one-pedal.

I'd like to mention that this has been a relevant issue for much much longer than what most know. Generation II aka XW20 Prius', years 2004-2009, have a "B" on it's shifter, this allows the Prius to apply a strong level of regenerative breaking (On a level road you can go from 60mph to 40mph in about 3-4 seconds.) Now it only applies the breaking when you let off the pedal completely so it's different there, but it does NOT light up the break lights. I use it to help charge my hybrid battery more and to avoid having to use my break on hills, but it definitely without a doubt confuses people behind me. I'll be going down a mountain with a 12% grade and can hold say 35mph perfectly without touching either pedal and if someone's behind me they'll typically fly up on me cause they think I'm just fully sending my car as my brake lights aren't lit.

The new Opel Astra Electric has a function that in the HUD informs the driver when the brake lights turn on and off in different situations, so you know what the car behind sees and doesn't see...

When I was a teen taking driver education classes, my instructor stressed that manual cars can decelerate by downshifting without engaging their brake lights so always be extra attentive to the relative distance between yourself and the person in front of you

While true, anyone braking a car or larger vehicle by downshifting wont have a functioning transmission for long~ Its a good back up method to slow down if your brakes fail but doing this often will almost guarantee an early trip to the shop~ *Before!* you comment to tell me how you engine break and automatics do this or that, maybe read the entire thread first....

Most people driving a manual you’ll hear downshift

@TheDigitalThreatwhat? Downshifting is done all the time on cars.. lol

@TheDigitalThreatsaves your brake pads, just buy solid transmission mounts to prevent worn out mounts

I drove a manual for 20 years. For truckers engine braking saves on pads. For cars you would be an idiot to risk your transmission over cheap brake pads once a year or two. Nobody driving an average car is engine braking in normal driving and if they are, they are an utter moron.

Just got a a new MG4, and did a test of the "one pedal driving", and can confirm the brake lights do automatically activate. I did a few runs past a person watching, and lifted of the accelerator as I passed them. It wasn't very scientific, but the brake lights do seem to activate for any amount of lifting off where the car is slowing appreciably.

Radar cruise on my '18 Lexus applies the brake light if the deceleration is enough. Pretty sure lots of other cars do the same. Also note that you could do something similar downshifting in a manual car up an incline. You need to always watch the car in front brake light or not.

This video got me to rig an inspection mirror to the brake light of my ID.4. I’m glad to say I’m satisfied that my brake lights illuminate in a safe manner in that vehicle in “B” mode.

As a driver of a car with a manual transmission, I've thought of this issue when engine braking. Usually this braking is not as severe as an electric car's regenerative braking, but I have had situations in which the car behind me could have benefited from knowing I was engine braking. Across the board, cars should have brake lights activated by deceleration no matter the source.

Our 2016 eGolf seems to use accelerometer based brake lights, but our 2018 Pacifica PHEV does not, so I have to drive that one in normal mode and use the brake pedal. I was also stunned when I found that Chrysler hadn't thought of this obvious safety hazard.

23:26 Thank you for converting the time to metric time. I was watching this with a friend from the UK, and it really helped him understand that 13 seconds US meant 13 seconds for him.

Common mistake, the UK actually uses a mix of metric and imperial, so 13 seconds is known as 13 seconds here.

Weird. Normally 15 seconds in the us is 16.7 seconds here

Relatively speaking, the seconds differ in duration because international dateline and England=mc2

this is technically incorrect since you've to add the time the light takes to hop over the pond. 😂 rumor has it, your British friend is still looking for this donut chain you told him about, but can't find a anything resembling your spelling 🤣

I agree. electric braking would be really helpful for hybridizing vehicles and improving both safety and performance. No CDL for more weight and control.

Did some research on my new car, and according to the manual most Corollas with Adaptive Cruise do turn on their brake lights when braking. Good to see that automakers are at least listening to the UN proposal.

Finally! The Hank Green fan to Technology Connections fan pipeline is complete!