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Sudden Unexpected Acceleration today

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That amount of acceleration is of course merely a design decision. Heck they could make it accelerate a lot harder than that still! And I agree... much too aggressive. It also needs to be smoothed/delayed. When I'm following a car that's setting my speed, it hunts around for that good follow distance WAY too much... and it does it all too aggressively. Indeed, it turns out that I'm still a much better driver that AP and TACC... provided nothing jumps out in front of my while I'm napping. But that's for another complaint thread. :)
It needs to limit the jerk (rate of change of acceleration). The other day I was following a motorcycle and the neural net kept losing track of it and locking on to the car in front of it. It would floor the throttle and get a few feet closer to the motorcycle, see it and then do full regen (maybe even some braking). Not smooth but I guess it's good for keeping the driver alert! And of course when you're following someone who uses the accelerator as an on-off switch TACC decides that it wants to drive the same way. I do wonder if a convoy of Tesla's were following each other if it would result in an uncontrolled oscillation.
 
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It’s sometimes hard to be sure an incident is misapplication of the throttle pedal. Thankfully here we have a confirmed attempt to apply the brakes which were “inoperable”...simultaneously with an unintended acceleration. Driver error.

If you weren’t able to reason that out on your own, fair enough. But if you actually DID reason that out, but still posted here to placate your wife or defraud Tesla, shame on you.
 
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It’s sometimes hard to be sure an incident is misapplication of the throttle pedal. Thankfully here we have a confirmed attempt to apply the brakes which were “inoperable”...simultaneously with an unintended acceleration. Driver error.

If you weren’t able to reason that out on your own, fair enough. But if you actually DID reason that out, but still posted here to placate your wife or defraud Tesla, shame on you.
I am still wondering why there is no mention of "she hit the brakes hard!" in this story. She was "about" to brake, and then suddenly...
The omitted information is certainly implied, but I'd love to hear the details. Either the brakes were attempted, or they weren't. If they were... well, they still weren't. But still. then we have that confirmed attempt to apply the brakes that you mention. Otherwise, I guess she just hung on and went for the ride.... That would take some steady nerves to stay off the "brakes."

Is the latest OP still listening? Or was that a single-post fly-by?
 
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The other possibility on the regen one could be lack of traction. I haven’t experienced it in my Tesla, but in my Volt, if you lost traction (pothole, whatever) while using regen, the car immediately would disable regen. It felt like being jetted forward when it happened.
When you start driving the car and every time for some reason there is no regen, all EV drivers who are so much used to regen will feel as if the car is accelerating when they lift their foot off the gas pedal. EV drivers expect the car to slow down when they take the foot of the pedal, and when it doesn't it gives an uneasy accelerating feeling.

Not saying thats what you experienced..

On my normal driving, I have a spot that causes this. There's place where I turn from normal road to a parking lot. There's funny dip in between, so while I'm turning and usually slightly pressing brake (so small actual brake + full regen), when one of the front wheel goes over the dip and loses contact it disables regen and it really feels like the car accelerates. Happens more than 80% sure on that same exact spot every time I drive there.


Wouldn’t a right turn enable TACC if you accidentally hit the stalk?

Yes I stand corrected, I guess it’s possible, I cannot rule that out, I did not feel it but it is still possible, I guess it would accelerate to the speed limit of the street if that happened and that would explain it.

Exhibit A: Wasn't one of the common problems on Model 3 that the turning signal stalk was too easily activated? Maybe your car has fairly easy TACC side too?

Exhibit B: My previous car, after about 3 months of ownership the wiper stalk became super sensitive. Pretty much when I hit any small pothole, it'd apply wipers. Railroad crossing -> wipers. Speed bumps -> wipers. It was kinda funny. Service tried to fix it few times, eventually replaced the stalk.

So in your case, the TACC sounds quite possible option.
 
On my normal driving, I have a spot that causes this. There's place where I turn from normal road to a parking lot. There's funny dip in between, so while I'm turning and usually slightly pressing brake (so small actual brake + full regen), when one of the front wheel goes over the dip and loses contact it disables regen and it really feels like the car accelerates. Happens more than 80% sure on that same exact spot every time I drive there.






Exhibit A: Wasn't one of the common problems on Model 3 that the turning signal stalk was too easily activated? Maybe your car has fairly easy TACC side too?

Exhibit B: My previous car, after about 3 months of ownership the wiper stalk became super sensitive. Pretty much when I hit any small pothole, it'd apply wipers. Railroad crossing -> wipers. Speed bumps -> wipers. It was kinda funny. Service tried to fix it few times, eventually replaced the stalk.

So in your case, the TACC sounds quite possible option.
I must have engaged it without even realizing it, once unintended acceleration occurred then I give myself a good excuse for not figuring out that it was my fault as all that was on my mind for a fraction of a second was STOP THE CAR! now that it has been pointed out that this has happened to many people and based on how my car behaved then NOW it seems like the only logical explanation.
 
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$100 to the charity of your choosing if you have logs showing a Tesla accelerated while the brake pedal was fully depressed.

Put me down for $500. lol.

--

Seriously, this thread is still a thing? Every claim here should just be met with an auto-response: "No, you're wrong. You, your wife, your husband, or whoever was in the driver seat at the time hit the wrong pedal. Accept responsibility. Get over it." *Closed*


Here's what I'll do. If you want to prove SUA, bring your car to my shop along with $10,000 cash. I'll have $10,000 cash as well. I'll pull the logs, verify they weren't tampered with, and decode them right in front of you. If you're technically minded, I'll even go over how exactly the speed and pedal position data is deciphered in Tesla logs.

If they show what I know they'll show (driver pressing the accelerator), I keep your $10,000 cash and mine and also make a public post detailing the findings.

If it shows that the brake was pressed instead, yet the car still accelerated, you take my $10,000 cash and yours. I'll additionally make an affidavit testimony of what I've uncovered and offer my services as an expert witness in any related litigation, free of charge. At your discretion, I'll post my findings publicly.

Still want to say you're right? Put your money where your mouth is and prove it.

If not, just get over it and move on.

Edit: Disclaimer - You can't win this bet. I'm 17 for 17 so far on log pulls related to Tesla SUA claims (most for insurance company contacts).
 
Edit: Disclaimer - You can't win this bet. I'm 17 for 17 so far on log pulls related to Tesla SUA claims (most for insurance company contacts).

Are you saying that insurance companies have been paying you to pull the logs because they didn't trust that Tesla was telling the truth? Or is this more of a "my client won't shut up about this not being their fault so to shut them up I'll pay an independent party to verify what Tesla has already told everyone." situation?
 
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Seriously, this thread is still a thing?

This will forever be a thing. In my experience *most* people today still think that Toyota had a serious "unintended acceleration" problem that killed all sorts of people and that Toyota was forced to fix this by recalling millions of cars.

The star example that blew this into front-page news was a veteran CHP officer and his family in a Lexus... an aftermarket mat pegged the throttle to the floor, everybody was killed in the high-speed crash off a bridge that ensued. They had the wherewithal and the time to call 911. But nobody mashed the brake pedal.

The 2009 Toyota Accelerator Scandal That Wasn’t What It Seemed

I can't tell you how many times I've hammered this message into my recently-licensed daughter. If the car is going faster than you want for any reason... use the brake pedal. If you're sure that you are already on the brake pedal and the car is not slowing... no, you are not. Remove foot from the "brake" pedal, think where the brake pedal is, and go again. You can't press too hard.

Everybody asks how to put the car into N, or how to turn it off. Or even how to call 911! Screw all that. Mash the brake pedal. And if that doesn't work, mash the brake pedal that's on the left. As far as I can tell, that has a 100% success rate in slowing or stopping the car.

Be sure to read this (linked from the above link) to see how this was first reported.. virally. "We have no brakes"... "crash caused by faulty Toyota accelerator." And yet it was a floor mat on the accelerator that would have been defeated by proper application of the brake pedal. Tragic. Sad. And wildly off the mark.
Toyota recall: Last words of father before he and his family died in Lexus crash | Daily Mail Online
 
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Are you saying that insurance companies have been paying you to pull the logs because they didn't trust that Tesla was telling the truth? Or is this more of a "my client won't shut up about this not being their fault so to shut them up I'll pay an independent party to verify what Tesla has already told everyone." situation?

Honestly, not 100% sure. My feeling based on the conversations is that it's the latter.

I think people just don't want to accept a key fact in all of these cases. With nearly 100% of vehicles on the road, Tesla included, the friction brakes can always overpower the powertrain, even full throttle acceleration. It's by design. If the car accelerates quickly, you weren't on the brake, and that's just a fact people need to understand, accept it, and get over it.

In the most juvenile and condescending tone as if there's a language barrier in a B-movie: If your foot on brake, car not move. Foot on brake. Car not move. Period.
 
I can't claim that I know the exact details of my recent, exciting situation... but at some point I suppose I could go test it in the same location. I sure wasn't going anywhere near 18 mph when my TACC engaged. I was in a *full* busy parking lot with cars all around me parked and moving. I was easing around a turn, around a pod of parked cars with no clear line of sight. I had light pressure on the accelerator pedal, and I couldn't have been going more than fast walking speed when I hit the Toyota-spec wiper stalk (the TACC activator in the Tesla). And woosh, I was off to the races. All of my attention at that point was on stopping the car. After coming to a stop (didn't travel more than a few feet, but of course that feels like a long distance when it surprises you!). It occurs to me now that there is no chime for TACC engagement, is there? I was just trying to recall if I heard a chime....

So. Yeah. There is definitely a way to engage at low speed when in a parking lot. I know that I've done it!

And I'll keep saying it. No Cruise Control should accelerate you automatically at the moment the system is set. And *especially* when it is this easy to inadvertently set.

There is a chance that it locked into something, like a parked car. Then accelerated toward it. But it should have stopped if it kept going to a stopped car.

Now, if the stopped car was “lost” by the Tesla turning (or it moving out of the way totally) then it may accelerate to the set speed???

Harder to test, but worth playing with.

Edit to add - now that I think about it, I think there is a speed range that it will lock. I know stopped. I’m not sure about anything between stopped and 18mph.

Now it might lock when one is stopped and driver not realize it. Then as they accelerate slowly into a spot the blocking car clears and TACC speeds up?

Again, more testing required.
 
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I have read the replies to the original post. Unless this has happened to you, it is easy to put the blame on the driver.
My wife and I have owned our Model 3 for 6 months. She drives it as much as I do. She has NEVER had an accident in her 30 years of driving. As with many, she was slowly pulling into a parking spot. She was utilizing the creep function, not putting her foot on anything as you do with these cars. She was about to put her foot on the brake to fully stop the car when it suddenly accelerated, drove over the parking curb, through a chain link fence, and into 2 parked cars. Thank God nobody was hurt. It happened so fast. She wasn't distracted, had nothing to drink and knows how to drive a Tesla.

I know that this will elicit "this is total BS, it is driver error, there is no way these cars do this, etc, etc." Hey, I love this car but all I can think is what if my kids had been standing in front of the car? On autopilot, it has done some screwy things, but I love autopilot for the most part. At this point, I'm selling it. Ok, now everyone tell me how stupid I am to post this, etc. I'm glad this doesn't happen very often, but for us, once is enough.

please read these:

More "unexpected" acceleration stuff... ugh.

Ok, first, the Model 3 logs are physically accessible on the logging SD card in the car PC, which is slightly less inaccessible than in the S/X. I've copied my own a while ago, and they're very similar to the S/X, although lots of IDs are redone. So, wouldn't be too difficult to check this with physical access to the car.

That said....... please just don't bother.

I just recently finished what I believe is my tenth private investigation of cases of "unexpected" acceleration in a Tesla where the owners have claimed the car accelerated on its own and they didn't press the pedal, yada yada.

Every single instance has shown that the accelerator pedal was physically pressed to the floor (or nearly) during the event. This is monitored by 100Hz reporting of the two sensors in the pedal by two independent systems (a "pedal monitor" and "drive inverter cross-check", only changes are logged... and this actually used to be 10Hz logging, but Tesla bumped it up probably in response to claims like this). If it were an electronic issue or the car just decided to massively accelerate on its own somehow (not actually possible, for the record), the curve of both sensors would not match perfectly with baseline logs of me mashing my own pedal. In every case I investigated the four logging points for pedal position changes matched perfectly with a physical pedal doing the exact same action. Every. Single. One.

After being unequivocally proven, the parties contracting me to somehow exonerate them have essentially begged me to not stand by my stance of publicly posting the data or sharing it with anyone. (If you may recall, I've offered to investigate such instances free of charge in exchange for the rights to basically do whatever I want with the data, including posting in relevant threads or stories.) Out of respect for those involved, I've honored such requests.

So, sorry for your accident, OP, but it's just not the car's fault. End of story.

Long story short, I think I'm going to stop wasting time on such investigations.

It likely has happened in other vehicles, you likely just had time to correct the mistake in your pre-EV vehicles. Unlike their sluggish ICE counterparts, the Model S/X/3 will immediately respond to a throttle request. You don't have the same time to react, consciously or unconsciously, to the mistake before action is taken by the vehicle. In the case of the S/X/3, you're likely to have moved the vehicle a significant distance prior to figuring out that you screwed up, where in an ICE, especially an automatic, the engine is likely to rev and gears need to be changed, yada yada, in response to the throttle mash... generally enough time to realize your error. I've almost made a pedal misapplication mistake several times in the past with multiple different vehicles... fortunately not in any catastrophic situation. We're not infallible creatures. You get in a zone of habit, feel like you know what's going on, and when something unexpected happens you'll swear you were doing everything normally the way you've done it 10000 times before, when in reality you just screwed up. It happens.

Tesla's accelerator pedal is actually the exact same drive-by-wire pedal used in several other manufacturer's vehicles. It's highly proven technology over decades. Nothing special at this point. No Tesla secret sauce here. Just two hall effect sensors with slightly different curves for redundancy and position validation. If they don't agree, the car doesn't move. If one has an issue, the car reduces power and gives an error. I've personally never seen one of these throttle assemblies have a problem because they're literally as basic as these things can get. It's plastic, a spring to return the pedal to rest, and two hall effect sensors for positioning. They're rock solid on reliability and used in millions of vehicles.

Tesla's side for sensing this goes even further to improve safety. They have two independent systems monitoring and logging the pedal sensors, isolated from one another. They both log the read position from both sensors. If anything doesn't exactly agree, the car doesn't move, gives an error, and reduces power to the point where you can barely do 0-60 in a minute.

The autopilot side of things also is not capable of accelerating the car at any major speed. The AP system just tells the motor, "this is how fast I want to be going and this is how quickly I want to get there" and the inverter firmware maps out a curve to get the car there based on the data, clamped internally to extremely reasonable values as far as acceleration goes. (Deceleration is another story, since AP is capable of commanding full regen and full braking.) The fastest AP can do 0-60 on its own is pretty pathetic, overall. I've tried it. The car will not launch even when commanded to go to 90 MPH at max longitudinal acceleration rate. It just gradually ramps speed, just as if you were at a light behind a vehicle with AP engaged. Nothing sudden about it.

I went a step further and modified the section of inverter code that limits the acceleration rate. No dice. The two other systems inside the drive unit immediately sent the system into limp mode when I tried to command massive acceleration digitally. To be able to do a full digital launch with no pedal application I had to modify the firmware in three different systems to bypass probably two dozen different safety checks. Long story short, it's simply not possible for the car to command massive acceleration on its own.

Going even further, the throttle map for acceleration is super accurate. It can interpolate 2^16 throttle positions with reasonable accuracy... which is impressive, since the ADC is technically something like 10-bit, and we're working with a throw distance of maybe a couple of inches at the end of the pedal. (Edit: Correction/clarification: The crosscheck ADC is 10-bit, the primary is actually 16-bit and doubled for redundancy on each input... so the throttle position is actually read 8 times in hardware for comparison.)

Finally, if the brake is applied, three different devices report this. There's the brake pedal switch, the iBooster, and the ESP modules. All are able to sense and report brake pedal application, and the three systems in the drive unit accept these in a binary OR fashion (if any report the brake is applied, the brake is applied). If the brake is applied even a tiny bit, the car is incapable of accelerating at full power. At best, if the accelerator is already pressed, the car will apply something like 5% of power for about a second before fully cutting power due to both pedals being applied. Those that think they had their foot on the brake and suddenly accelerated, try it yourself. Go somewhere safe with open space in front of you, apply the brake, and mash the accelerator. You'll either go no where, or at most move at super low power for less than a second (depending on the exact internal state of the system, which would be too complicated to get into full detail here).


Overall, I have a lot of beef with Tesla over many things... but this is one aspect where they did their homework and did it right. I'd argue that Tesla's throttle setup is probably at least twice as safe if not more than any other drive-by-wire throttle system out there. There are some many independent checks that it is just impossible for the car to do something like full acceleration without the drive explicitly commanding it, either intentionally or unintentionally, via the throttle pedal.


Of course, humans are going to human... and thus never fully accept responsibility for their actions or mistakes when there is a way to push that onto someone or something else. But my advice is to just get over it, keep the car in chill mode, and move on. In this particular case, your wife made a mistake, caused some damage to the vehicle, and that's the end of it. No sense trying to argue otherwise... especially in the case of a Tesla vehicle with its extensive logging and redundancy. Should someone ever take such a case to court and try to go against the data, I couldn't see how a reasonable judge or jury could possibly see this as anything other than what it is.
 
The pedal discussion reminds me of a post on /r/justrolledintotheshop.

It was a picture of an owners accellator pedal completely covered by the floor mat with a dirt stain where the owner has been pushing to drive the car. The owner had no clue this was unsafe.

Also, TACC and autopilot should never activate if the car is below a certain speed. I can’t resume the CC On my gasmobile until it exceeds 25-30 mph. No automatic driving system should engage froma stop.
 
Seriously, this thread is still a thing? Every claim here should just be met with an auto-response: "No, you're wrong. You, your wife, your husband, or whoever was in the driver seat at the time hit the wrong pedal. Accept responsibility. Get over it." *Closed*


Here's what I'll do. If you want to prove SUA, bring your car to my shop along with $10,000 cash. I'll have $10,000 cash as well. I'll pull the logs, verify they weren't tampered with, and decode them right in front of you. If you're technically minded, I'll even go over how exactly the speed and pedal position data is deciphered in Tesla logs.

If they show what I know they'll show (driver pressing the accelerator), I keep your $10,000 cash and mine and also make a public post detailing the findings.

If it shows that the brake was pressed instead, yet the car still accelerated, you take my $10,000 cash and yours. I'll additionally make an affidavit testimony of what I've uncovered and offer my services as an expert witness in any related litigation, free of charge. At your discretion, I'll post my findings publicly.

Still want to say you're right? Put your money where your mouth is and prove it.

If not, just get over it and move on.

Edit: Disclaimer - You can't win this bet. I'm 17 for 17 so far on log pulls related to Tesla SUA claims (most for insurance company contacts).

All threads re: SUA should just redirect to this single post (the quoted one, not mine).
 
What I don't understand is why they are standing on the hood? Having opened the door on a car in river, wouldn't you keep walking toward the bank? Why move toward the rear, close the door, then walk around the front to stand on the car?

#atleastigotaselfie
Yeah the article says the river is shallow, so they were able to get out. So doesn't make sense why they don't just walk on shore. Seems like a publicity stunt.
 
I tried to bring reason to the comments section. I've determined that it is impossible. Because, you know, maybe the pedal sensor is wrong.

In any of these stories, all you have to do is read up to the point where it says "I used the brakes" and then stop. After having lived through the Toyota debacle, I'm just SO done with user error being blamed on the car. We keep giving it airtime as if it is reasonable to consider. And the idiots in the comments section suck it right up. Electrek should strive for a higher standard than "I will give the driver the benefit of the doubt."