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Sudden Unexpected Acceleration today

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Hi Folks,

Long time TMC lurker, however first time poster. I wish my first post would have been about the excitement of getting my M3. However, I have a much serious topic to post about.

Today while out for shopping my wife met with an accident in the parking lot of a grocery store here in Chandler, AZ. She is badly shaken up. Issue occurred while trying to park the vehicle in a parking lot of a grocery store. The vehicle was in the parking space position when it suddenly accelerated without any input from her. She said she applied the brakes, however they felt inoperative. It felt as though the driver had no control over braking and the vehicle had a mind of its own.

She turned the steering wheel to avoid directly hitting a dumpster while trying to brake. The passenger side of the vehicle then hit a curb and a concrete wall. After the impact, she managed to turn the vehicle while applying the brakes that eventually brought the vehicle to a stop.

My wife called Tesla, however they were of not much help. The service center individual instructed my wife that they could not tow the car to the service center given the car had suffered damage and they can only accept cars after the damage has been fixed. Not in the state to argue, we called our insurance and had our car towed to a Tesla authorized repair shop.

I know there are several cases registered with NHTSA and I even found class action lawsuit against Tesla regarding sudden or unintended acceleration, I feel mine is the first case of a Model 3 with behavior that has been seen with S or X several times. What is surprising that EVERY instance of this case has pointed to driver error. I find it ridiculous to dismiss people reporting a serious security flaw with a vehicle to saying - the logs show 100% accelerator press by the driver as the car will NOT do ANYTHING the driver does not intend for it to do. Then how do you explain an individual's reaction to STOMP on the wrong pedal while they are trying to ease into a parking spot?? - it is illogical and irrational to ever surmise that a driver's who's so familiar with the concept of regen braking will press the (wrong) pedal so hard that the car would suddenly accelerate like crazy.

What she went through today is very disconcerting and unsettling. My confidence in cutting edge technology is shaken that helps Tesla to beat other automakers in making technologically forward vehicles. I have been a software professional my entire career and can understand bugs / glitches in the Software. It is one thing to not be able to control volume of the radio of my car (as it happened last night while driving from our friend's house, the left scroll button kept moving the steering wheel even though the option was not enabled), it scary to even think of the car doing what it did! The consequences could have been catastrophic. I am thankful that she is safe as there was the wall protecting her from cross traffic on the main street.

Please be careful, cognizant, and caring of your loved ones.

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...she applied the brakes, however they felt inoperative...

Sorry to hear about the accident.

Tesla warranty does not cover collision so car insurance needs to cover it including any towing.

As you can see, by default, it is much easier to apply the accelerator pedal which is positioned lower to the floor and it takes more effort of lifting your foot higher from the floor, much higher than the accelerator pedal before you can reach a brake pedal.

This happens in any gas or electric vehicle but an EV has an instant torque and instant acceleration so drivers may be taken off guard.
 
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On the bright side, the damage doesn't look too bad compared to others where misapplication of the throttle caused a crash.

The car does log the voltage of both potentiometers that measure the throttle pedal position - one of them increases in voltage as the pedal is applied, the other decreases in voltage. It is a redundant anti-symmetrical system so If the logs show both agree on a time-increasing pedal depression the there really is no other plausible explanation than that the throttle was mistakenly pressed when the brake was intended.

If you don't believe Tesla's reading of the log, you can hire Jason (@wk057) to pull your logs (not sure he can do that with the 3 yet).
 
Brakes are normal hydraulic power brakes, if the driver stomps the brake, they clamp down like any other car.

On top of that, this car, unlike most gas cars, electronically cuts power the instant the brake is touched even if the accelerator is pressed. Try it.

The brakes can easily overpower the motors. See youtube videos of super cars being held stopped by brakes while the rear tires are smoking and melting.

Sorry - if the brakes were pushed, the car would stop. She pressed the accelerator, it happens!

Sorry for your loss, hoping for a speedy repair.
 
If you're really confident that it wasn't user error then I'd advise getting the car back directly after it's fixed.

Then use a dashcam as a footcam.

So if it happens again than you'll have video evidence of what happened.

With my Model S I have the opposite problem where sometimes I accidently hit the brake. Never severely, but probably once every three months I'll glance it.
 
Claims of unintended acceleration aren't just limited to Tesla vehicles. So please let's not make this into a story about Tesla specifically having an unintended acceleration problem. Check the logs. If the logs show the accelerator was pressed, then the debate is about whether the logs (both in general and specifically for Tesla if there's some hardware difference) can be wrong or your wife is lying/misrecalling. Sorry, but that's just the truth of the matter.
 
Did a quick google search and there are plenty of hits for unintended acceleration for every make and model. I have another theory...

Many of these scenarios may be related to medical conditions such as seizures, muscle spasms, fatigue, medication, etc., If the driver is unaware (certain seizures), he could understandably believe the car accelerated on its own. If the driver is aware, he could also understandably claim the car accelerated on its own because there are very strong incentives for not reporting/acknowledging the medical condition as the cause. For example, his driver's license could be revoked or severely restricted. Insurance rates could go up. His job could be at risk. It's just easier to blame the car.
 
On the bright side, the damage doesn't look too bad compared to others where misapplication of the throttle caused a crash.

The car does log the voltage of both potentiometers that measure the throttle pedal position - one of them increases in voltage as the pedal is applied, the other decreases in voltage. It is a redundant anti-symmetrical system so If the logs show both agree on a time-increasing pedal depression the there really is no other plausible explanation than that the throttle was mistakenly pressed when the brake was intended.

If you don't believe Tesla's reading of the log, you can hire Jason (@wk057) to pull your logs (not sure he can do that with the 3 yet).

Thanks for the contact Hacer. There's not much information on what throttle Tesla has on the Model 3. Assuming they are shared between the three models, it should have the same redundancy or lack thereof as in the S and X.

Will have to see what log data Tesla shares with the owners.