How Does Brake-By-Wire Work? Plus: Audi e-Tron Sportback Review!


Is Brake-By-Wire Safe? First drive in the 2020 Audi e-Tron Sportback!
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Audi's e-Tron Sportback features brake-by-wire. What is brake-by-wire, and is it safe? In this video we'll look at the technology and engineering involved with brake-by-wire, talk about why it's done, what benefits it has, and what failsafes exists in case of emergency situations. Brake-by-wire ultimately uses electronic control of the disc brakes. But if things go wrong, there's still a way to stop the car. Check out the video to learn all about it!
From Audi's Press Release:
"New for model year 2021, the Audi e-tron model lines receive impressive revised packaging, including attractive entry pricing with a new Premium trim level. As a result, the e-tron SUV is offered at $65,900 starting MSRP for the model year 2021, a decrease of close to $9,000 from the starting MSRP of the model year 2019 Premium Plus e-tron. The e-tron lineup also receives a number of technical spec enhancements for improved utility. Through optimized drive system hardware and software adjustments, the 2021 e-tron achieves efficiency improvements resulting in an EPA-estimated range of 222 miles, an increase of 18 miles. Meanwhile, the e-tron Sportback delivers an EPA-estimated range of 218 miles.
As technology progresses, the e-tron lineup has seen its most significant improvements with available battery capacity and efficiency. For a more efficient configuration, thanks to a number of optimizations, the front electric motor is able to be entirely disengaged, dramatically reducing power usage when not needed. Only when the driver demands more power or traction do both motors spring into action, providing the surefootedness of Audi quattro® technology and the powerful dynamics Audi is known for.
In addition, the usable amount of the high-voltage battery has increased for the model year 2021 e-tron lineup. The battery in the Audi e-tron and e-tron Sportback have a total capacity of 95 kWh and now gives customers access to a net energy figure of 86.5 kWh- almost 3 kWh more than 2019 e-tron model. The energy buffer is designed to help ensure customers enjoy sustained battery performance throughout the life of the vehicle.
Enhancing the charging experience are dual charge ports on the driver and passenger side of the vehicles, newly available on the Premium Plus trims of the e-tron and e-tron Sportback."
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  • RickitySplitz
    RickitySplitz7 dager siden

    Too overly complicated for something like this.

  • Kevin Mills
    Kevin Mills8 dager siden

    So it’s a second car for local urban running around? How much does it cost?

  • Richard Kuil
    Richard Kuil18 dager siden

    more sensors means more faults......

  • odysseyrider1
    odysseyrider129 dager siden

    Lmao the thumbnail😂😂😂 bro

  • William V
    William VMåned siden

    Great job on your animated illustrations!

  • HECKproductions
    HECKproductionsMåned siden

    i think it's a bad thing how this tries to be more "beginner friendly" because that has lead to people not being able to solve even the simpelest problem on the computer like i use a program that needs java runtime enviroment and when you first fire it up it literally says "browse the path to your jre folger here" and "if you don't have one download it from" and then a link to java dot com it's so simple a child could do it but most people i know weren't able to do if for the life of them i'm afraid that in like 30 years a car will be warning about tyre pressure and the average dumbass user is gonna be like wAt iZ tYrE

  • CSLFiero
    CSLFiero2 måneder siden

    braking with a potentiometer is a terrible idea in sim equipment, so it's a terrible idea in an actual car.

  • Dreigo42
    Dreigo422 måneder siden

    Can I get one of those pedal simulators in my sim rig? That'd be pretty cool...

  • Rennie Allen
    Rennie Allen2 måneder siden

    So Columbo would have his work cut out in 2020 because he would be able to find any brake fluid on the driveway that indicates that Mr Keppel cut Mr Norris's brake lines. Cutting some wires leaves no telltale evidence in the driveway.

  • Cody Schleiger
    Cody Schleiger2 måneder siden

    Would never buy one of those used LMFAO. Money pit of death!

  • rootsid
    rootsid2 måneder siden

    I live in Iowa, the weather here is horrible one either needs heat or air conditioning most of the time. How much will that 220 mile range suffer?

  • zoperxplex
    zoperxplex2 måneder siden

    Typical German engineering: take a relatively simple system and make it more complicated and expensive. Wait a few more years and the German auto industry will be assuring you that drive by wire is a safer system as well.

  • No one Important
    No one Important2 måneder siden

    Just FYI my 16 camaro I hit 0.8 gs braking

  • kashyapa fernando
    kashyapa fernando2 måneder siden

    So is it basically when the electronics brake system computer detects less than 0.3 g’s it will slow down the vehicle using the regenerative system while charging the battery 🔋 and once detected more than 0.3 g’s it will open a valve and activates the mechanical brakes using hydraulic brake fluid?

  • MXT
    MXT2 måneder siden

    How about we make cars where you plug and play your wheel into or like I do with my pc

  • Clickmaster5k
    Clickmaster5k2 måneder siden

    A smaller battery with less range but less weight so more efficiency and faster charge time would be way better for around town. Gota look at miles per min of charge more than just all out miles.

  • John Smith
    John Smith2 måneder siden

    I LOVE BBW :) oops wrong video..

  • mobilemowers
    mobilemowers3 måneder siden

    Over complicated computers taking over all the braking. Now another system you can't work on at home unless you have expensive diagnostic equipement. Then replacing the expensive leectric parts when they fail much less really be bale to test them. Shot nowadays you need a scanner just to replace the parking brake or bleed the brakes. I hate to see it shorts out while driving or simle jump starting the car shorts it out. So sad most people can't even on thier own cars and have to spend $125 plus an hour to get it fixed. Then thier 20% mark up on parrts. Keep it simple. This video should be called over engineering explained.

  • G
    G3 måneder siden

    If this is how the industry defines "brake by wire", then it is brake by wire. Simple.

  • Reynaldi
    Reynaldi3 måneder siden

    i mean MGU-K works well for F1....

  • Audun
    Audun3 måneder siden

    Set a custom charge finish level: Press vechicle on the MMI display -> Charging and efficiency -> Charging -> Press charge level indicator , then adjust "Charging target". Valid levels are 50-100 in incriments of 10

  • FutureSystem738
    FutureSystem7383 måneder siden

    ETron’s efficiency sucks- just say it!

  • Specialopsdave
    Specialopsdave3 måneder siden

    I drive a hybrid without brake-by-wire, so the regenerative braking has no pedal resistance and feels weird

  • hunter alber
    hunter alber3 måneder siden

    okay thats is true

  • Lawrence Fearon
    Lawrence Fearon3 måneder siden

    Kindly thank your neighborhood Mercedes R230 SL for introducing Brake-By-Wire to the world in 2001.

  • HowManyTabsYouGotALot
    HowManyTabsYouGotALot3 måneder siden

    '"Some say he uses four limbs to control each brake, and one eyebrow for turn signals. All we know is he's called the Stig!"'

  • mgsboedmisodpc2
    mgsboedmisodpc23 måneder siden

    a double episode

  • Patches33001
    Patches330013 måneder siden

    I’d rather not put my trust into some wires that will eventually short out

  • Basilhs T
    Basilhs T3 måneder siden

    It has a front grill, CUTE !

  • Johnmichael Quinlan
    Johnmichael Quinlan3 måneder siden

    Everyone wants the biggest range, its not the length its how you use it !!!! :D

  • Nicholas Scanlan
    Nicholas Scanlan3 måneder siden

    oh boy, just another thing to brake

  • Nick Byrd
    Nick Byrd3 måneder siden

    “, the oblivious consumer...” 🤣

  • double-you
    double-you3 måneder siden

    wow that will break, knowin' its an audi.

  • Zac Jarvis
    Zac Jarvis3 måneder siden

    5.5 seconds for the 0-100k sprint? Pretty sure my 98 wrx does just as good if not better.

  • Zac Jarvis
    Zac Jarvis3 måneder siden

    Every mechanic watching this is straight panicking knowing your life is in the hands of a sensor.

  • Weeaboo Patrol
    Weeaboo Patrol3 måneder siden

    In the camera world, we have 2 types of mechanics that we use to focus. Fly-by-wire and mechanical focus. Guess which one professionals always use? Mechanical. The precision and accuracy in a mechanical set-up gives the operator more control and feedback than an electronic device.

  • dnz vpr
    dnz vpr3 måneder siden

    You are good engineer. Please Could you explain how hyundai imt transmission works. İ am really interested in this transmission.

  • Miguel Angel Vizuet Mata
    Miguel Angel Vizuet Mata3 måneder siden

    So if this fails, are you sure you won’t be geobraking?

  • Raymond Alamo Jr
    Raymond Alamo Jr3 måneder siden

    Dude - I love your video! Keep it up!

  • David Leonoff
    David Leonoff3 måneder siden

    Are those shift paddles on the steering wheel? Huh?

  • AirRatchetJockey
    AirRatchetJockey3 måneder siden

    So it’s basically a standard hydraulic system with electric assist vs vacuum.

  • Robert Clements
    Robert Clements3 måneder siden

    You seem smart. How come you haven't come out for Thorium yet?

  • Ryan Davey
    Ryan Davey3 måneder siden

    What controls braking if your car is off, let's say a scenario where the battery dies and you need to push it?

  • MorrisJ 2000
    MorrisJ 20003 måneder siden

    People get mad when you call an electric motor an engine, but by definition it is: "a machine with moving parts that converts power into motion"

  • Christian Thomas
    Christian Thomas3 måneder siden

    The CD isn't an absolute number. It's proportional to the frontal area. That's why it doesn't go as far.

  • Hudson Hornet
    Hudson Hornet3 måneder siden

    A lot of people don’t realize brakes only slow you down in life

  • Erinn McCrankypants
    Erinn McCrankypants3 måneder siden

    Whoa whoa whoa audi! You haven't even graduated past making a door handle that doesn't immediately break maybe we should take baby steps on designing the future of brakes...

  • FalconXE302
    FalconXE3023 måneder siden

    "Is it safe"... quite possibly the silliest question have have asked Jason... LoL... just joking. But yeah... if it has found it's way into a lot of road going cars... I am quite happy that "it is safe". Great video Jason... as always very interesting

  • Cornel Bogdan Macrineanu
    Cornel Bogdan Macrineanu3 måneder siden

    But for that valve to open, what do you need? Is it electrical? If so, no thank you.

  • Chris Bradbury
    Chris Bradbury3 måneder siden

    What a roundabout way to brake.

  • guits
    guits3 måneder siden

    Mercedes did electronic brakes years ago. Worst thing that happened was that you ended up in limp mode I think. There was an extended warranty and stuff not lasting long enough so I think they reverted back to just ABS for most cars and I'm not sure they still use it at all now. Or have a different system.

  • Brulaap Gaapmeester
    Brulaap Gaapmeester3 måneder siden

    What if a mouse shits in your potentiometer and the cat that chased it eats the fail safe system instead of the mouse?

  • Valtteri Wikström
    Valtteri Wikström3 måneder siden

    I think that there should be full mechanical or hydraulic connection after something like 75% of pedal travel. Without that there's too many things that can fail. I would feel unsafe driving older car with pure Brake-By-Wire technology. Some system checking whether or not the others are working can give false positives.

  • Peanut
    Peanut3 måneder siden

    Lol... why do we feel the need to be sophisticated? Plus, imagine working on these new cars.

  • midnightgolfer
    midnightgolfer3 måneder siden

    range matters

  • RichRusso4218
    RichRusso42183 måneder siden

    Just a way for Audi to make their cars even heavier and slower.

  • Ryan I
    Ryan I3 måneder siden

    So what is the purpose of brake by wire on non-hybrid or electronic cars? I have the Alfa Romeo Giulia and although I like the brakes a lot, I've wondered why they went by wire with them. Especially if there is a back up hydraulic system, then you're not even saving weight...

  • RichRusso4218
    RichRusso42183 måneder siden

    If it is on an Audi, it is going to fail, quickly.

  • Tango Trike
    Tango Trike3 måneder siden

    He looks like a highschool/college student. And also a father at the same time.

  • Andrew Seger
    Andrew Seger3 måneder siden

    Hey Jason, can we get a video on your thoughts as to why the Ferrari F1 team is doing so poorly, and possible reasons behind the massive performance losses we are seeing in their car this season? Donut just did a video but I'd love to hear a more technical point of view.

  • Gacheru Mburu
    Gacheru Mburu3 måneder siden


  • HmongGuitarPlayer
    HmongGuitarPlayer3 måneder siden

    Well if the that fail you will wish you have a hole through the floor board so you can do a Fred flinstone braking.

  • Chris S.
    Chris S.3 måneder siden

    The base model epa rating is done with the base aero wheels. I assume the sportback version comes with nice wheels as standard since it is a design over function car anyway. So that would explain the lower range rating. Funny business with standard wheels and efficiency ratings is common in the european market.

  • Y B
    Y B3 måneder siden

    Is there a way to submit requests for videos?

  • Fuse
    Fuse3 måneder siden

    Classic german engineering. Lets take something simple that works and complicate the hell out of it no good reason whatsoever.

  • Paul Son
    Paul Son3 måneder siden

    This sounds horrible

  • Regenmeister
    Regenmeister3 måneder siden

    More over engineered electronic crap...

  • mravecsk1
    mravecsk13 måneder siden

    Crazy low range for big BP like this. Because of that it charges very fast at the expense of battery "lifespan" and degradation. Also remnats from ICE that make no sense in an EV. So, it is nice car but not realy good EV.

  • phil spencelayh
    phil spencelayh3 måneder siden

    By the time I got the the end I had forgotten that the film was about "Brake by Wire" . It had got back to range anxiety as always with electric cars, which really isnt a real problem to most people who have enough money to spend $70,000 on a shopping car and keep another with decent range for when you actually need to go a bit further afield.

  • crosstheborder731
    crosstheborder7313 måneder siden

    300 mile range? *Laughs in 30 y/o V8 Mustang

  • Mike Hat
    Mike Hat3 måneder siden

    Ètron is turd in French.

  • LTVoyager
    LTVoyager3 måneder siden

    And ICE cars only need a 5 gallon gas tank most of the time. However, occasionally you do and that is why they have 15+ gallon tanks. EVs are no different. There may be times you come home and your power is off all night and you need to drive another day on your battery without an overnight charge. Or you need to evacuate from a hurricane and need the range. Tesla got it right going for range as close as possible to existing ICEs. To do otherwise is not very smart if you want to gain any market share.

  • LTVoyager
    LTVoyager3 måneder siden

    This is fairly old technology. My 2007 BMWK1200LT has a system nearly identical to this, sans the regen obviously. Nothing new to see here.

  • james becker
    james becker3 måneder siden

    OMG... thank you for bringing up the FACT that in 90%+ of the family situations, people do not need a 500 or 600 mile range EV. 150 or 200 is overkill for most people. The car will be lighter, cheaper, and more can be made since they are not hogging so many battery cells. The typical consumer drives only 20-40 miles per day. Not 300.

  • Calvin W
    Calvin W3 måneder siden

    Thanks. I hate it.

  • KRAUSER0130
    KRAUSER01303 måneder siden

    Don't get me wrong, VW/Audi fanatic here :D but what was wrong with regular brake system? This is just complicated and unnecessary = expensive to make and get fixed once something goes bad in it. Hydraulics is doing pretty good job for the last.. 50, 60 years? And basically entire system is some kind of failsafe, so if we are going to mention redundancy.. Well that's just my opinion. Things are being more advanced and modern, BUT is it always for the better? Maybe I am too old-school and but one thing will never go out of fashion; if you don't have it, it won't fail! Well, cool looking Audi, I have to give it that, BUT the only thing that it's missing is TDI version. I never cared THAT much about emissions and soot and NOx.. Yeah diesel this, diesel that.. But my 1.6 turbo diesel can go for over 800 miles with one tank of gas, burns less fuel than a lighter! But nobody cares about all the gasoline engines that are often burning 3 times more fuel than what I just mentioned, AND for some reason that's okay, but what do I know... However Audi said they don't plan to say goodbye to diesel engines any time soon despite electrification, so I'm good ;)

  • Michael Gia Huy Nguyen

    Michael Gia Huy Nguyen

    3 måneder siden

    If you're driving an high-end car like Audi, you should be able to afford the service done on these cars anyway

  • Four utubez
    Four utubez3 måneder siden

    I'd expect the braking pressure to be measured by a load cell rather than position sensor ? Or did I miss something ?

  • David Smedley
    David Smedley3 måneder siden

    I have experienced the tandem motor that powers these kinds of brakes fail on a 2017 Accord hybrid (there is now a recall for it). Let me just say thank goodness for the parking brake. Even standing on the brakes all I got was ABS vibration and practically no braking force. I would never buy a hybrid again or a Honda for that matter.

  • Maza
    Maza3 måneder siden

    If it is basically a hydraulic system then why npt run ot like that. No need for all those electronics.

  • Jordan Ketterer
    Jordan Ketterer3 måneder siden

    I was thinking if a EV with independent four-wheel drive were Ariel couldn't have a pretty good amount of attitude adjustment through gyroscopic and rotational Force each wheel could independently move and break accordingly to be able to change the attitude of the vehicle to better land and keep people safe in case of high speed collisions

  • BBKing1977
    BBKing19773 måneder siden

    If you use only regen braking, do you risk premature corrosion of rotors due to lack of use?

  • Francisco Shi

    Francisco Shi

    3 måneder siden

    I am doing an ev conversion. I am having two motors one for front and one for back. So far I have been tesing the drive train on a rolling chassis that has no brakes (no master cylinder and no brake pedal) and so far with only half of the available regen I can drive like a normal car without ever having to reach for the brake pedal. Some one once saw me driving and asked me how did I get the brakes to work without the master cylinder. So I am certainly going to have to deal with the issue of rusting rotors. I have considered getting them chrome plated but not sure if that is a good idea.

  • Engineering Explained

    Engineering Explained

    3 måneder siden

    They will get enough use to keep the rotors clean each time you drive, even if you barely touch them.

  • Green Goat
    Green Goat3 måneder siden

    Mercedes tried this, and it sucked for some very unavoidable reasons. Don't glorify a safety hazard

  • where's fillman86
    where's fillman863 måneder siden

    Not going to fail? I seem to remember Toyota having to do a recall on this exact type of system

  • dafff08
    dafff083 måneder siden

    all these people scared of electronics. what about steer by wire? its a thing for quite a while now. never heard of any problems because of it. the problem is not electronics, its poor build quality and lack of redundancy.

    IL MOSTRO3 måneder siden

    My Model 3 gives me around 200 miles max and I’ve never needed to supercharge in 1.5 years of ownership. Warm weather months I charge to around 75% a day and during the winter I charge to around 85% a day, and it’s always been more than enough for my daily 90 mile work commute including lunch trips and occasional full throttle fun. In other words, range anxiety isn’t something I ever have. And if I’m in trouble, I have superchargers all over the place. You just need to plan slightly if you know you’re going on a longer trip the next day, just set it to more charge that night. You simply think of your garage as the “gas station”. I’ve charged to 100% maybe twice in 1.5 years.

  • justinl458
    justinl4583 måneder siden

    2 of the most misspelled words on NOlocal that piss me off is *Brake* and _Break_ and *Lose* and _Loose_ Really shows how many people are dumbass degenerates who are ignorant.

  • Paul Bailey
    Paul Bailey3 måneder siden

    I had a 37 Ford that was brake by wire

  • Chasing Dragons
    Chasing Dragons3 måneder siden

    Can you go back to doing your homework and explaining things honestly? Firstly you are driving an AUDI. Check the price tag for a second. I realize as an engineer you are accustomed to this idea that you get paid well enough to afford toys but for goodness sake actually explain to people the real reason brake by wire hasn't made it to the US yet. It's called the LAW. For example, according to FMVSS 121 a compliant pneumatic system MUST be on a commercial truck. This makes EBS EXPENSIVE to field in the US. No commercial fleet is going to willfully spend MORE money on something that ultimately does the same thing... stop the truck. Current braking systems, if they could be measured in horsepower on an 80,0000 / lbs vehicle would clock well over 9000 horsepower. You are driving an AUDI. It can have effectively TWO braking systems because it is EXPENSIVE. Honest. This video is about as bad as the time J Leno mistakenly said the Chrysler Turbine Car never caught on because it didn't like LEADED fuel... which isn't WRONG entirely... it just skips right over the inconvenient part where the jet engine produced a pathetic 130 horsepower, the fuel economy was as bad or worse as a V8 of the same vintage, but it was 10 TIMES MORE EXPENSIVE. Sources: Heavy Duty Trucking System, Sixth Edition by Sean Bennett, pgs. 1023-1024 Drive: The Definitive History of Driving, pg. 215

  • rocko44444444
    rocko444444443 måneder siden

    There are lots of airplanes with drive-by-wire system, without any major issue. I don't see a problem to use in cars. Excluding Boeing 737 MAX.

  • Evan Angeletos
    Evan Angeletos3 måneder siden

    Not made to last.Expensive to maintain and repair.

  • DJMMAS14
    DJMMAS143 måneder siden

    So what if the valve don't open and I can't brake.....

  • Chris C

    Chris C

    3 måneder siden

    Lawsuits happen then

  • David
    David3 måneder siden

    my problem is the fail safe valve is closed until there is a problem. Giving that most people don't change the brake fluid that valve could get gummed up, so say at a 150,000-200,00 miles something in the system fails the valve tries to open but cant. Then what? you're fucked that's what.

  • sanjinred
    sanjinred3 måneder siden

    Perhaps you should outline that the main difference is that electric cars dont have a conventional vacuum system. Hence the electronic system. They still have brake fluid.

  • BlueDually4x4


    3 måneder siden

    Its hydro boost that uses an electric motor to run the pump instead of taping into the power steering pump.

  • yungeen trn
    yungeen trn3 måneder siden

    Wait so how does abs work?

  • Tommy V
    Tommy V3 måneder siden

    If only Tesla could put some effort into their interiors so enthusiasts can enjoy their cars too

  • Paulo Mesquita
    Paulo Mesquita3 måneder siden

    About you remarks of range and use cases, I live in Lisbon, Portugal and over here there are many Uber drivers that use NIssan Leaf or Renault Zoe cars with 240Km range or less and most of them are happy with their cars and are profitable (and they use essentially old models with less range than the new models of this year). So even with this very specific use case is possible to have "low" range EV with not too much nuisance. But in the end it all depends on the personal feeling.

  • Damien Koh
    Damien Koh3 måneder siden

    Hi, have you made video for spark plug? Does normal spark plug has huge difference with iridium spark plug? What are the different?

  • RockawayCCW
    RockawayCCW3 måneder siden

    Does a V6 have the same natural balance as an Inline 6?

  • QuantumS1ngularity
    QuantumS1ngularity3 måneder siden

    I hate the fact most manufacturers are still going after battery powered EVs and it's only Honda and Toyota who are pursuing the real EVs with HFC. I wish companies like VW which invest billions upon billions on RnD looked towards the HFC technology and infrastructure. I'm a calm, cool and collected man, but i can't wait to refuel a car for 40 mins to an hour every 250-300km. It's simply unacceptable. Also living in Europe kinda makes it hard to own an EV when you park on the street 90% of the time with a car that eats through its own fuel while sitting still (especially in the winter). So giants like VW, just need to keep making the ICE cars they know all too well and focus the RnD money on finding the best way of collecting and storing hydrogen so we can all finally shut the mouths of all ecomentalist and make them finally see that the problem was never the car in the first place.

  • intellectual Raccoon
    intellectual Raccoon3 måneder siden

    what if the valve fails .. "Guess ill just die"

  • intellectual Raccoon

    intellectual Raccoon

    3 måneder siden

    "You Died"

  • narancs5


    3 måneder siden

    You can use the E-brake. Oh, wait, E stands for electric now, not emergency.