My dad tapped a car because his brakes stopped working. Tesla denies anything wrong with car but sent the vehicle data requested. How to interpret?

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Use ChatGPT. Tell it what it is and ask what it sees. End every sentence with “in the file”. Then go from there.  When did car brake. When did it come to standstill. When was impact registered. Any data on accelerometer.  You can also tell it a persona. I’m a accident inspector, investigating a car crash. I have this log file and need to extract relevant information in an understandable way.

There is a good chance that your dad didn’t actually tap the brakes, people make mistakes.

What do you mean?

The logs I looked at confirm that he did indeed press the brake pedal.

So isn’t that your answer?

I would think so but Tesla is saying they found no evidence of an issue despite the logs showing that my dad pressed on the brake... It's not that easy with them unfortunately

You're right! I actually tried that as one of the first things. Even ChatGPT says that it's likely that something went wrong with the brakes from the data. I tried Grok and Google Gemini as well and they said the same. But I try not to hold too much weight when it comes to AI opinions

Are you willing to share the log?

You’ve hit a dead end without a lawyer. Tesla will absolutely lie and mislead you to save a few bucks, it’s led by Elon Musk after all.

Chat gpt will agree with what ever you think.

I am 100% willing to share the log if you are willing to look at it and could suggest the best way to share it

How hard? Is there a signal like “brake pedal position” or pedal angle? Is there an acceleration measurement? Anything referencing brake torque or regeneration torque?

Yeah good to be critical. Ask it to organize data without changing content. Maybe as timeline of key events about braking.

Post it on Google Drive and right click the file and make it accessible to people who have the link

There are no brake pedal position or pedal angle variables. Gas pedal position was at 0 the whole time. I'm not too sure about torque

I uploaded it to Google Drive. I don't feel comfortable publicly posting it where everyone can see it. Can I DM you?

Sure, send it over

Can you share the file? You could share a link to Google Drive to DropBox.

Do the logs show a change in deceleration after brake activation?

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How detailed is the data in the last couple seconds prior to impact? People would be better able to help if they could see the data, though I saw in another comment you're uncomfortable sharing it publicly. This excerpt from a recent NHTSA-reported incident involving an Ohmio Lift autonomous driving system shows the type of data that might be useful: >\-Upon detecting the minivan in the side envelope, the system issued a brake command within 5ms. >\-Brake pressure began rising 58ms after the command and exceeded 90% of the requested pressure 164ms after the initial command. >... >\-The elapsed time from first detection of the minivan in the side envelope to impact was approximately 358ms. >\-The vehicle came to a complete stop in 1.178 seconds. >

Tesla won’t admit fault bro even if it’s true you have to force them

Just hitting the brakes doesn't mean much without more context. How soon before the moment of impact did he hit the brakes? I've been in an accident where my tires were screeching from hitting the brakes before impact.

I'm not too sure how I would be able to tell looking at the logs.

Sure. I will DM you the link.

We are unable to tell not seeing the logs also. Seems you have some others looking for you.

If I showed you the logs, would you be able to give your opinion on the timeframes?

I read about an expert with a fair amount of experience decoding Tesla logs, although I think lawyers and experts charge enough that unless there's an serious injury or death, it would cost more than it's worth. If you can't get the issue addressed, I'd try to sell it to a Tesla dealership, and tell them what happened, so your conscience is clearer if the next owner dies from the issue.

Can I share the data with you?

How do you force them?

Regen braking slowed my dad to 9.4 kph (their logs are in kph) when he hit the brakes. 3 seconds later his speed went down to 0 when he hit the car. Considering that he tried braking hard, 3 seconds is an awful lot to slow down from from \~5 mph, right?

Would I be able to send you the CSV file of the logs along with the relevant timeframes?

Share the log?

Is the brake pedal all on or all off, so even if you gently tap it it brakes as hard as possible, or does it have variable sensitivity like in most cars, so the harder you press the harder it brakes? If it has variable sensitivity, and Tesla won't share that data, I think you're stuck. Knowing your dad pressed the brake doesn't mean it was pushed all the way down. Even if he was pushing hard, a temporary obstruction could have interfered with depressing it all the way.

Can I DM you the CSV file along with the relevant timeframes? I'd rather not share it publicly on reddit.

Sure, go for it.

Lawyer

Sure, I just sent a DM.

Well ‘pressing the break’ does not necessarily ‘stop’ a car - though it should always slow it down, and eventually stop it. Unless the car is moving very slowly, it can’t stop instantaneously.

What do you mean by variable sensitivity?

Sounds like it did what it could.. ideally it should have detected an impending collision sooner and have taken action sooner..

Like if the braking acts differently depending on whether the brake pedal is depressed a half inch, one inch, or two inches. In many vehicles, you can gently depress the brake pedal a little bit and the vehicle will very slowly move forward, so you can control the vehicle speed with the brake pedal instead of the accelerator pedal.

The car was moving at around 5 mph at the time...

If you're talking about creep, the Tesla doesn't do that

There are no cars with on/off brakes. All cars increase deceleration with added pressure to brake pedal. If Tesla only gives a Boolean value, they’re hiding information.

Look up the law firm currently suing Tesla over the fsd and other issues. Share the data and camera footage once you have explained

There are some lawsuits going on now, regarding Phantom braking.

Phantom braking is autopilot/fsd braking when there is no obstacle. So unexpected braking, not lack of braking.

What’s phantom braking?

Yeah, it sounds like Tesla is only giving the state of brake lamp switch that’s attached to the pedal. That’s pretty useless without correlated accelerometer data, which should be continuously tracked by the vehicle’s stability control system.

It’s Tesla. They actively don’t care.

Shit is why you run a backup dashcam in your Tesla.

If hydraulic brakes work now, they worked then. Possible issue is obstruction under brake pedal. Sometimes, if work is done on the brake system, and they aren't bled correctly, you could get a spongy pedal requiring a pump or two to brake. This would still be evident in driving the car currently if it were an issue.

Tesla never takes responsibility for their vehicles flaws.

Are they suing over anything brake related?

But this is something that could easily be deadly in the wrong situation

Brakes are a physical thing, if the pedal doesn't work, it's not going to start working again suddenly.

I am not an expert. It is something your insurance company would be interested in. If it can be demonstrated the brakes failed then they me be able recoup their losses from Tesla.

Actually its a bit more complex with a car with blended braking. The pedal isnt connected to the hydraulic system directly its all computer controlled. What signal the computers sent to convert the brake pedal position to the hydraulic brakes vs the regenerative brakes is a good question. Once software is making decisions works now doesnt mean worked even 5 seconds ago.

This isn't an insurance matter. Thankfully nobody was hurt and no cars were damaged. It's more of a safety matter since there is potential for this to happen again in a high-speed situation.

they might if you bring it to their attention!

where the car slams on the brakes in the middle of the highway

That is autopilot braking when it shouldn’t. Much different than hydraulic brakes failing.

Shall I post some thoughts here, or in DM? No VIN, just a summary of what I'm seeing. It's pretty basic, you probably notice the same thing, but just to make sure we're on the same page.

Yeah that's wild. You'd think you'd want to keep the hydraulic active no matter what for emergencies.

Oh gotcha. This isn't a phantom braking case. It's quite the opposite actually.

So they have even more incentive to pretend nothing is wrong and hide shit because it could be evidence in another case.

i wonder if the issue is that , since most people never use brakes in a tesla (just regen "one pedal" operation), that the brakes were just rusty/dusty and stuck?

What do you suggest my dad does about that then?

My dad frequently uses FSD though. As far as I'm aware, FSD uses the physical brakes more.

This is false.

welcome to driving a tesla! lol. they dont care. and if you send them an email, they reply with a poop emoji. have you been looking at the news of tesla and elon musk for the past 6 years? he went insane.

you never heard of an air bubble in the lines ?

Im not an expert in Teslas or anything like that i mainly dealt with blended braking in rail. In rail at least we have backups upon backups so if the computer doesnt do the right thing there is some sort of fail safe system that will automatically take over. I would hope the brakes on a car have a similar system but Tesla in particular seems to shun such things. See their doors for example. I drive a Kia EV currently and I know from experince after the computer gives the brakes a clean every now and then the hydraulic brakes almost never engage outside an Emergency level stop. Regenerative braking is used almost exclusively in normal operation. 45 thousand kms into ownership me brake pads are still over 90% of original thickness.

Something seems off here. This type of failure is extremely unlikely. Tesla's current vehicles use an off-the-shelf braking system made by Bosch. The software is custom-made for Tesla and calipers/pads are from other suppliers. The primary system uses an electric motor (iBooster) to boost driver-provided brake pressure or to produce its own brake pressure (e.g. for autopilot/fsd braking, hill hold, etc.). It also has electronically controlled valves for directing brake pressure to individual wheels for vehicle dynamics control and abs. However, by design, none of these features can remove driver-applied brake pressure. In other words, there is always a direct mechanical path from the driver's foot to applying brakes at the wheels. If the brake boost were to fail, you would see multiple alerts pop up on the UI and the car should still stop, but the driver may need to press the brake pedal much harder than they are used to. If there were no alerts on the screen, then the only thing I can think of that would prevent the car from stopping would be an obstacle in the driver footwell physically preventing the brake pedal from traveling. You may want to check for this.

Brakes are a very powerful hydraulic system. They are going to get stuck on after hydraulic pressure is relieved if they’re corroded, not stuck off despite hydraulic pressure being applied.

and if the rotor is slick because its never been used/covered in dirt and the pad cant get a grip on it ? or if theres a stone stuck in it

Short of a very expensive legal fight? Tesla wont roll over they will spend serious amounts of money and do outright illegal shit to hide things as has been proven in past legal cases. Honestly wearing the cost of the accident and taking a loss trading the car for something else is probably the finacially smart decision. Even if your 100% sure its faulty. Not many people can afford to fight on their principles when facing a litigious and very wealthy company...

Lawyer time. Tesla will never admit to a problem unless forced by a court, and even then they will try and make it go away. Dishonest company, good luck

What type of lawyer even deals with this?

Not necessarily. ABS pumps can indeed malfunction and cause these kinds of issues. I’ve seen it first hand with a new JL rubicon. Watched a guy climb a long vertical slab (think rock formation that climbs about 4 stories in about 100ft). He got to the top and needed to back up a few inches to maneuver over. I’m at the bottom of the slab filming. He is on the brakes hard. He puts it in reverse and the jeep takes off down the slab uncontrollably. He pushed the brakes as hard as they would physically push. The brake lights never went out. Whole jeep went to the bottom where it flipped. Long story short, the jeep actually went back to Chrysler for investigation and they never did figure out why it happened. There was no mechanical problem to be found but the video was clear as day showing there was a failure. Chrysler gave him a new jeep and paid him a settlement though since he was injured in the roll over. Everyone’s best guess is the ABS module sensed some kind of slippage since he was off road and caused the ABS pump to cycle into bypass. Fluke electrical failure or programming glitch in the modules software.

All 4 calipers get a stone stuck? You can have glazed pads or even pads that don’t have friction material. They’re still going to add pressure and stop. This is most likely an abs pump or abs module problem

Sell the car ASAP. Tesla isn't going to admit to anything no matter what you 'prove" because it would open them to potential future liability. Your only other option is hiring a lawyer but that is just going to cost you money. Tesla has unlimited legal resources and like all big corporations their strategy will be to bleed you of legal expenses until you quit. Your only real option is to not do business with shady corporations like Tesla. Sell the car and move on.

The brake in Tesla is not brake by wire (almost no cars are). It’s the same as any other modern vehicle where the brake pedal drives the master brake cylinder hydraulically. The brake force is proportionate to the pedal force, so even if the logs show the brake was pressed, it doesn’t show how hard it was pressed and whether it was pressed hard enough. It can’t possibly be a software issue that caused this, if it was brake failure.

Selling it doesn’t sound morally correct though

That’s because in automatic ICE the engine is always spinning and in a typical automatic transmission box, the torque converter has enough torque to push the car forward even at idle, so letting your foot off the brake will propel the car forward (and you can feather that to achieve very slow speeds). EVs don’t do that because there is no spinning engine idling. It’s either accelerating or it isn’t. This is entirely independent of the brake system which IS similar to ICE.

My dad couldn’t gently tap the pedal even if he tried. The logs show the car took 3 seconds to go from 5 mph to 0 mph with the brake pressed. Brake pressure never went above 6 bar

Unless you can somehow prove the brake pedal force, then you’re out of luck. The brake system is very rudimentary in every car deliberately (power failure safety) and brake force will always be dependent on a physical issue, not a software one.

Get in contact with the firm that have won several FSD cases already, they caught Tesla hiding data from crashes.

Tesla's main brake operates like any other car's without regenerative breaking, to have a better braking feel, so I doubt the issue would be EV or electronics related.

Heh, yeah. Notice how you're getting downvoted for saying things that are totally appropriate and normal, but just happen to cast Tesla in a negative light? That happens on reddit, like, to the point that it's noticeable. You will very likely find yourself banned from the 'official' Tesla subreddits soon, especially if you posted about this incident in other ones. The mods of those subreddits monitor any mention of Tesla and are quick to ban anything negative. (The most likely explanation is because they hold Tesla stock and deep down they know their salad days are numbered, and are desperate to keep the music playing while there are still chairs left.) Elon Musk is Not a Good Guy, and everything he touches has significant ethical compromises. Tesla doesn't have a PR department because Elon thinks that if he just never talks about bad news, then whatever that bad news is about may exist, but it doesn't matter. Distressingly, so far he seems to be correct about that.

Do you happen to know the firm?

https://www.singletonschreiber.com/ Here's the first case https://electrek.co/2025/08/04/tesla-withheld-data-lied-misdirected-police-plaintiffs-avoid-blame-autopilot-crash/

The only issue is that there weren't necessarily any monetary damages to sue for. I'll suggest the firm to my dad so he can try calling them but I have a feeling they might not take the case.

Well, it's not. More to the point, in most jurisdictions selling something knowingly defective without revealing the defect can make you liable for any subsequent issues. In this case since Tesla said "no problem found" you might be OK, especially if you're clear about that when you sell it "we thought there was a brake issue but Tesla's mechanics investigated and told us there's nothing wrong".

Bear in mind that this is a Tesla, so brakes don't work like normal cars. I don't know much about Tesla brakes, but somewhere in the system there has to be something which decides if regenerative braking is going to happen when you press the pedal, or if hydraulic braking will happen. If that thing doesn't work right, and it's trying to do regenerative braking at 2mph (which would have no effect) instead of hydraulic, then I think you'd see what the OP experienced.

So are Tesla’s autonomy products, their insistence on pushing all controls onto a touchscreen, and their reworking of decades of reflex development for the sake of one-pedal driving.  There’s a reason why I have no qualms about calling them the most serially negligent company in the world.

You only have one way forward from here. First, buy Tesla stock for everything you got. Then go to the world wide media and blow the story up how shit Tesla actually are Then watch the stock go up by 10%. Sell everything and retire

Lol really?

Which is why they are the deadliest brand. Tell your family to not drive Teslas.

I'm not sure OP knows they're on a sub designed to trash Tesla.

Take the hit, subscribe to r/RealTesla and move on.

I actually do know that. I figured I’d get the best advice here compared to a place with Tesla loyalists

Creeping at different rates with a brake pedal is a sign of a variable brake pedal input, but braking with different power is also a sign of that. Depressing the pedal to the max, for example, should apply maximum braking, while depressing the pedal just a bit should apply just a bit of braking. It sounds like Teslas do have that, but the level of braking is not recorded in your log, perhaps (personally I think *probably*) intentionally because it could show that the vehicle braking didn't work properly.

Awh, ok.

DM me them so I can always refer to your thoughts if I need them. But if you’d like you can definitely post them here too!

The master cylinder pressure is recorded if that counts

At minimum, FSD _has already_ been deadly. At least one case has had a jury verdict, a rather large sum iirc. I don’t know if there have been successful brake cases but your issue has definitely occurred to others in the past.

Check with a good lawyer FIRST. They might take the case, or refer you to one who has cases like this in their wheelhouse. Some have said that the litigation would be expensive. Not necessarily. Plaintiffs’ lawyers often take cases on contingency. That means their fee is some fraction of the eventual award. Used to be around 30%. So they don’t get paid if you don’t win. A good attorney would evaluate your case, including any evidence you already have, and tell you whether you have a (potentially) winnable one. Initial consultations are often free. What people have said about Tesla’s duplicity and litigiousness is absolutely true. That will dissuade litigation especially if the case is not strong. Only a good experienced attorney can make that call with any accuracy. (Edit: and upon reflection, and being reminded that you don’t have a lot of damages might make the case hard to take.) I also respect your moral issues with selling a potentially deadly vehicle. It’s a tough situation. It’s also part of the damages you can claim. Check with your state’s bar association for referrals and also just ask around. I’m not encouraging you to litigate. It’s a tough road. I _am_ encouraging you to check with a _good_ attorney to evaluate your options.

the logs they sent you are incomplete on several levels: - it only comes from the "gateway" and it filters signals and only records them sporadically. - they don't even fully interpret all the signals that are contained in there The full-full logs would be on an autopilot snapshot if one was generated, but good look getting them to even admit they received it. I had a somewhat similar issue on my car: after confusing the gear (being a new Tesla user at the time) I accelerated in wrong direction, quickly realized my mistake and stomped on brakes, only for the car to beep at me with "brake fluid low" or some such. Needless to say the slowdown was a lot less than I expected and I narrowly avoided entering a building via a window. The brake assist remained non-operational afterwards for the rest of the drive. So I called up the service center and they took the car in and declared they don't see anything wrong, it took me showing them various internal logs (that I happen to have access to) for them to come up with some (who knows how made up) explanation of the event: "we think it might be was an air bubble in the lines so we bled them and you are good to go now for sure" The other thing to consider is if you(r dad) use the default stopping mode for brakes and never press brakes normally, the moment you actually need the brakes they might not be in the best shape because there's some accumulated residua on the disk and what not.

Shouldn't simple Automatic Emergency Braking engage in these kinds of scenarios? Did that fail to engage? Guessing it was going too slow for it to trigger?

I am sorry about your scary experience. If you don’t mind, I have a few thoughts and questions: 1. My dad wasn’t on autopilot. Could a snapshot still have been generated? 2. Did the vehicle data logs show the brake light going on for you? 3. What internal logs did you access and how? 4. My dad uses FSD often which I know uses the physical brakes more.

There was an AEB unavailable error in the logs right before the crash

yes, snapshots are generated when conditions are met, like n airbag deploy, aeb and a whole bunch of others. Of course when you did not have a very clear event like airbag deploy/pre-deploy it's harder to predict if it happened or not and only Tesla really knows. Yes, of course I got the brake light and the brakmng was there, just losing pwer assist greatly decreased the braking force. But the light is actuated by a switch at the pedal if I remember the diagram correctly, so it's entirely possible to get the light even if the brakes themselves don't work (Though that's unlikely). 3. The logs back then were just a log of alerts. That's before the times where you could just go into the service tab and see recent alerts.

This is an important insight. Brake master pressure is provided as a real value. Perhaps this is sufficiently equivalent to the brake pedal position (which is not provided, only on/off).

well that right there is suspicious enough… I’ve seen AEB trigger when it feels like a garage ramp is too steep.

Yes, legal action is expensive and can take years. Dump the car, and look around for a lawyer that is willing to work on contingency.

Drive-by-wire is a lovely thing.

So how do I get Tesla to do something?

Unfortunately I don’t think you can in this case… Maybe just drive the car yourself for a few weeks so you can assure your dad its working ok. Might’ve been a 1 time thing hopefully.

I am about to move a few hours away so I’m in a situation where it would be a bit hard for me to do so

No Tesla is brake by wire. It’s a mechanical connection with a master cylinder like all cars. The regen is a separate thing dependent on the motor decelerating. The brakes will work even if the car is completely dead - you’d still get one or two good pumps out of the master cylinder.

An expensive one. I will warn you, lawsuits are money pits. A cheap lawsuit will cost you $50k and typically bleed you 1.5-3 years. You can easily spend 6 figures on legal fees trying to fight a company like Tesla.

Don’t most lawyers work on a contingency basis though?

No, not good ones. A good lawyer is gonna charge you for every 1:10th of an hour at $300-500 an hour. It’s usually $10k to $15k up front as a retainer just to start the case. Then another $8-15k for a trial retainer if you don’t settle. Plus the other 50-100 or so hours in between that they’ll bill you for. You’ll probably have 150 billed hours wrapped up in a lawsuit. If you’ve ever been on the civil side of the legal system you’ll realize it’s a rich man’s game. Big companies will do everything in their power to bleed you dry trying to get you to give up the case. They have whole legal teams that are on the payroll who will make sure your lawyer stays busy. If you do find a lawyer who works on contingency, they’ll take a large portion of the settlement.

So what if my dad can’t afford a new car or a lawyer? What would you recommend he does?

Buy a 2003-2006 Camry with about 200k miles for $2k-3k. Extremely reliable cars that are dirt cheap and simple. High miles is not a big deal. Get the Tesla fixed from the fender bender maybe it doesn’t need anything? Whichever but get it sold and then buy another car of his liking. Keep or resell the Camry.

There wasn’t any damage to the car. But the scary part is what if this happens again at a faster speed. It wouldn’t be morally right to sell the car in this situation

My best guess is it needs an ABS module or ABS pump. I would sell it to someone like Carmax or Carvana. But the morality of that is on your part to decide. Either way. An old Camry is money well spent when you need safe reliable transport and don’t have a lot of money.

. . .and be prepared to wait several years for Tesla to settle.

Shouldn't Tesla fix it if a two year old car is having that issue?

I had a colleague with brake failure on a model 3. The first thing he did after insurance paying for the crash, and hearing he'd be out of his car for at least 3 months was to order a real car, a Mazda.

Tesla vehicles do not have blended braking, unlike other EVs. That is why they push so hard for one pedal driving.

This firm is suing Tesla https://www.walkuplawoffice.com/2025/11/07/walkup-partner-andrew-mcdevitt-discusses-lawsuit-against-tesla/

Tesla and Elmo do not care. My advice: sell that piece of junk while you can.

I'm sorry to find this funny but Tesla gives zero fucks about driver/rider/bystander safety. 60 Minutes Australia did a piece about the lack of safety of FSD that includes reporting on a case where Tesla withheld data that the courts had directed them to hand over. OP, I'd watch this. While it may not be informative of what steps you should take it may give you a more realistic view of the company you are up against [60 Minutes Australia piece on Tesla](https://www.youtube.com/watch?v=d_apmcDJGS8)

I don't even trust the logs. How often is my Tesla not recognzing indicator stalk or fwd/rev stalk. In this case the logs just would pretend I did not trigger it. And I had a similiar thing where forward reverse got so messed up at parking that it said I need to press the brake to select a gear while I was fully pressing the brake pedal. As for the mentioned accident it would need a severe ABS failure to prevent the breaking. ABS failure should give a warning. So if there wasn't a warning the car was probably not aware about the failure and the logs will show nothing. On the other hand the car does not give a warning when high beams become unavailable in auto mode as well - imho a violation of legislation but Tesla doesn't care much about functional safety.

It might be a good idea to get the breaks inspected (maybe there is rust or the cylinders are corroded) and have the break lines purged. Could also be an issue with the break lines. I'd go to a third party repair, just because I don't trust Tesla.