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What is going on with those Model 3/Y Accidents in China / Paris ?

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I did a Twitter on this.


If I ever get the time, I'll try to do a video debunking all of the SUA claims with log data, hardware analysis, software analysis, etc... but that's a tall order I probably won't have the time for any time soon.
It should be easy enough to verify or deny this part:

When the [steering] motor requires over 100 amps to turn the wheels while the vehicle is stationary, the 12-volt system experiences a voltage drop to near zero volts.

Just hook up an oscilloscope or fast voltage meter to the 12V steering wires and see if there is a voltage drop when it's hard cranked while stationary like he theorizes. Also check the 12V supply at other places. Does the 12V drop low any point for any other reason while the car is operating (4 window switches hit at once, while AC cycled, etc?)

Is anybody able to video that test?

Edit: oscilloscope is best, the timescale may be milliseconds or less, if it happens at all
 
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Odd. This user is able to accelerate from 60 to 110 km/hr while the message "Both pedals pressed, Motor power reduced" is displayed. Presumably they are holding the brake and accelerator but there's no video of the pedals, they may just be slightly holding the brake pedal. But that would still start heating up the brake pads if you're continuously riding them at high speed.

Doesn't prove that they were unable to stop the car, but does seem to indicate that the car doesn't always kill power or prevent accelerating when you touch the brake pedal, while you're at speed. I think. I don't know how else we're supposed to interpret this video.

 
Odd. This user is able to accelerate from 60 to 110 km/hr while the message "Both pedals pressed, Motor power reduced" is displayed. Presumably they are holding the brake and accelerator but there's no video of the pedals, they may just be slightly holding the brake pedal. But that would still start heating up the brake pads if you're continuously riding them at high speed.

Doesn't prove that they were unable to stop the car, but does seem to indicate that the car doesn't always kill power or prevent accelerating when you touch the brake pedal, while you're at speed. I think. I don't know how else we're supposed to interpret this video.

How hard is that person pushing on the brake? Looks like it barely is depressed.
 
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How hard is that person pushing on the brake? Looks like it barely is depressed.
You're probably correct that the brake pedal is barely being pressed in this contrived test. Should that make a difference? Isn't the detection of brake+accelerator supposed to mean something? Just suppose the brakes have been ridden for some time and faded.

According to Tesla:
Likewise, applying the brake pedal simultaneously with the accelerator pedal will override the accelerator pedal input and cut off motor torque, and regardless of the torque, sustained braking will stop the car.

This car has not cut off motor torque, it's allowed to keep accelerating despite the car noticing that both pedals are depressed. Clearly the driver is just trying to prove a point, and could control the car at any point, it's not in danger in this video. But the point might still be valid, why is the motor torque NOT cut off?
 
You're probably correct that the brake pedal is barely being pressed in this contrived test. Should that make a difference? Isn't the detection of brake+accelerator supposed to mean something? Just suppose the brakes have been ridden for some time and faded.

According to Tesla:
Likewise, applying the brake pedal simultaneously with the accelerator pedal will override the accelerator pedal input and cut off motor torque, and regardless of the torque, sustained braking will stop the car.

This car has not cut off motor torque, it's allowed to keep accelerating despite the car noticing that both pedals are depressed. Clearly the driver is just trying to prove a point, and could control the car at any point, it's not in danger in this video. But the point might still be valid, why is the motor torque NOT cut off?
Because hill starts are required for people on steep hills, something I used fairly often before I switched to and got used to Hold. That's why a very light brake application shouldn't cut off the motor completely.

Note brake fade has nothing to do with it, there is a brake pedal sensor, which is unaffected even if the brakes are completely shot. If the driver is only lightly touching the brake, they aren't really trying to bring car to a complete stop.
 
Because hill starts are required for people on steep hills, something I used fairly often before I switched to and got used to Hold. That's why a very light brake application shouldn't cut off the motor completely.

Note brake fade has nothing to do with it, there is a brake pedal sensor, which is unaffected even if the brakes are completely shot. If the driver is only lightly touching the brake, they aren't really trying to bring car to a complete stop.

But the brake pedal only has one sensor response: Pressed or Not Pressed, unlike the accelerator which has full scale response.

So based on Tesla's wording, if the brake pedal is pressed slightly or fully it's all the same to the warning system. Brake pedal pressed in any amount + accelerator pressed = reduced motor torque.

Now if you're suggesting the Tesla is also considering pedal depth or braking force is being considered, where is it getting that from? Maybe the brake booster? If so then the Tesla is ignoring light brake application - which goes against what they are claiming in their safety response system. A light brake application should cut motor torque just as a heavy brake application, if the system is using the brake pedal sensor.
 
But the brake pedal only has one sensor response: Pressed or Not Pressed, unlike the accelerator which has full scale response.

So based on Tesla's wording, if the brake pedal is pressed slightly or fully it's all the same to the warning system. Brake pedal pressed in any amount + accelerator pressed = reduced motor torque.

Now if you're suggesting the Tesla is also considering pedal depth or braking force is being considered, where is it getting that from? Maybe the brake booster? If so then the Tesla is ignoring light brake application - which goes against what they are claiming in their safety response system. A light brake application should cut motor torque just as a heavy brake application, if the system is using the brake pedal sensor.
Doesn't what they state say "applying both pedals simultaneously"? i.e pressing both at the same time. I think that quote is about someone's foot being over both pedals and mashing them together.

There are different responses if you press and hold one, and then press the other afterwards. (For example, launch mode.)
 
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But the brake pedal only has one sensor response: Pressed or Not Pressed, unlike the accelerator which has full scale response.

So based on Tesla's wording, if the brake pedal is pressed slightly or fully it's all the same to the warning system. Brake pedal pressed in any amount + accelerator pressed = reduced motor torque.

Now if you're suggesting the Tesla is also considering pedal depth or braking force is being considered, where is it getting that from? Maybe the brake booster? If so then the Tesla is ignoring light brake application - which goes against what they are claiming in their safety response system. A light brake application should cut motor torque just as a heavy brake application, if the system is using the brake pedal sensor.
That's a very general one sentence statement that does not fully describe how the system works. I know for a fact that there is still torque (not zero) available when both pedals are used and this is required for smooth hill starts (unless you get used to Hold mode like I did where I know how to modulate the accelerator pedal). It may be very low, but it still exists.

I was basing my comment on memory, but doing a search @MP3Mike is correct that it works based on order (doesn't change however my point that brake fade wouldn't affect the sensor).

According to Tesla’s then-PR chief, Simon Sproule last fall, “If the brake is detected as pressed after the accelerator is already pressed (brake over-ride condition), the motor torque is reduced to zero at fixed rate.”

“If the accelerator is detected as pressed after the brake is detected as pressed (“both-pedal press” condition used for hill start, by drivers using both feet), the current motor torque is limited to no more than 250 Nm.”

“However, with hill start control now standard on all cars (from the software release in April), this is becoming less common.”

“Whenever the brake is no longer pressed, in either case, the torque returns the accelerator position requested torque at a fixed rate.”

The article author argues to remove second mode completely. But it was never removed (for good reason, not everyone likes the hill hold, plus hill hold does not address all scenarios, for example backing downhill).

You can see the Model 3 still has it:
If accelerator is applied and brake after, it says "Both Pedals Pressed / Motor power removed".
If brake is applied and accelerator after, it says
"Both Pedals Pressed / Motor power reduced".

About the brake sensor, I remember now where I saw it, it was discussion about China brake failure claims. The iBooster Tesla uses has a differential pedal travel sensor (which can definitely detect more than just on or off as it's used for regen brake blending in hybrids and some EVs), although Tesla doesn't record the detailed readings in the EDR (only as on or off):
ibooster_diagram-jpg.658853

 
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If accelerator is applied and brake after, it says "Both Pedals Pressed / Motor power removed".
If brake is applied and accelerator after, it says
"Both Pedals Pressed / Motor power reduced".
It doesn't explain why the fellow in post #64 is able to accelerate from 60 to 110 km/hr while that warning message is being displayed and his foot is on the brake to some degree. Shouldn't reduced motor power prevent that kind of acceleration? Yes, he could press the brake harder but the point is he is pressing the brake and the accelerator, the car notices this, and yet the car accelerates.


The commonly held response if you look for "Tesla brake and accelerator at the same time" seems to be people feel that the car will not allow it, and the car will come to a stop. However it seems that in various cases it does allow both to be pressed - with various different responses depending on the situation.

In other words we are back to the beginning of the problem with the brake and accelerator being used at the same time.. The car decides whether to override the driver's foot on the brake, and in some cases it allows acceleration.

Thus brake pedal + accelerator does not always kill the motor nor even does it always reduce the motor, in fact... it depends on speed, amount of force, car mode, etc, sometimes it will even accelerate.

Now we have nullified the safety rule of "driver decides" and we're back to "the car decides".
 
It doesn't explain why the fellow in post #64 is able to accelerate from 60 to 110 km/hr while that warning message is being displayed and his foot is on the brake to some degree.
But it does! He was already braking and he applied the accelerator after, which means "power reduced" not "power removed". You can see that process clearly on the video and screen.
Shouldn't reduced motor power prevent that kind of acceleration? Yes, he could press the brake harder but the point is he is pressing the brake and the accelerator, the car notices this, and yet the car accelerates.
No, it should not, because the car needs to be able to accelerate up a hill from a standstill! That's the whole point of this mode. It is not acceptable to cut all power just with some brake application. In a real emergency he would have applied more brakes and it'll come to a stop because the brakes would easily overcome the reduced torque. If he releases the brake and applies it again it would also activate the override mode.

The commonly held response if you look for "Tesla brake and accelerator at the same time" seems to be people feel that the car will not allow it, and the car will come to a stop. However it seems that in various cases it does allow both to be pressed - with various different responses depending on the situation.

In other words we are back to the beginning of the problem with the brake and accelerator being used at the same time.. The car decides whether to override the driver's foot on the brake, and in some cases it allows acceleration.

Thus brake pedal + accelerator does not always kill the motor nor even does it always reduce the motor, in fact... it depends on speed, amount of force, car mode, etc, sometimes it will even accelerate.

Now we have nullified the safety rule of "driver decides" and we're back to "the car decides".
No the driver still decides based on the order he applied the brakes vs the accelerator. The car only sets an upper limit in the second mode, but again it is the drivers decision how much torque is applied based on the accelerator. The "brake override" is intended to prevent the situation where the accelerator is stuck and the driver tries to brake. This has how all the fatal incidents have been. It is not intended to prevent you from using the accelerator after the brakes are already applied.
 
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It doesn't explain why the fellow in post #64 is able to accelerate from 60 to 110 km/hr while that warning message is being displayed and his foot is on the brake to some degree. Shouldn't reduced motor power prevent that kind of acceleration? Yes, he could press the brake harder but the point is he is pressing the brake and the accelerator, the car notices this, and yet the car accelerates.


The commonly held response if you look for "Tesla brake and accelerator at the same time" seems to be people feel that the car will not allow it, and the car will come to a stop. However it seems that in various cases it does allow both to be pressed - with various different responses depending on the situation.

In other words we are back to the beginning of the problem with the brake and accelerator being used at the same time.. The car decides whether to override the driver's foot on the brake, and in some cases it allows acceleration.

Thus brake pedal + accelerator does not always kill the motor nor even does it always reduce the motor, in fact... it depends on speed, amount of force, car mode, etc, sometimes it will even accelerate.

Now we have nullified the safety rule of "driver decides" and we're back to "the car decides".
I don't get why that's so hard to understand. "Reduced" power is not no power. Going from 500HP to 250HP is "reduced" power but it's still 250HP, for example. Most cars don't even have 250HP.
 
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I don't get why that's so hard to understand. "Reduced" power is not no power. Going from 500HP to 250HP is "reduced" power but it's still 250HP, for example. Most cars don't even have 250HP.
LOL. That statement is not as safety conscious as perhaps you intended. If your numbers, which are likely picked at random, are taken into consideration. What is being said here is "if you press both pedals at once, the car will still give you more power than most cars have in total.". We're not talking about getting up a steep hill after stopping in this scenario, this guy is accelerating on a road from 60 to 110 km/hr after the car has realized he has both pedals pressed. I fail to see how this is migrating the both pedals pressed issue.
 
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No the driver still decides based on the order he applied the brakes vs the accelerator.

If he releases the brake and applies it again it would also activate the override mode.
Are you listening to yourself?

The ORDER of the pedals being pressed? The driver has to release and reapply the brake?

The whole point of this system was to prevent accidents that occur because the driver has failed to realize that they have both pedals pressed. Now you want them to realize that they have pressed them in the wrong order and also they should release the brake and reapply it. If they could do that then we wouldn't need this override in the first place. These drivers have gotten into a situation that their brains can't figure out and they are riding both pedals. They aren't going to think about order and releasing, they are stuck. Thus the safety override.

If there are use cases for setting up launch control and hill hold, fine, allow that scenario to proceed, likely to say 10mph, on a hill start. But once that has concluded, don't allow the car to continue accelerating off. You're not still hill starting at 60mph. If you've got both pedals pressed, even slightly, at street speeds then warn and cut the motor power enough to actually slow the car. Otherwise what is the point of the safety system if it doesn't slow a speeding car?
 
Are you listening to yourself?

The ORDER of the pedals being pressed? The driver has to release and reapply the brake?

The whole point of this system was to prevent accidents that occur because the driver has failed to realize that they have both pedals pressed. Now you want them to realize that they have pressed them in the wrong order and also they should release the brake and reapply it. If they could do that then we wouldn't need this override in the first place. These drivers have gotten into a situation that their brains can't figure out and they are riding both pedals. They aren't going to think about order and releasing, they are stuck. Thus the safety override.
No, you are still not getting the point. The point is to address incidents where the accelerator pedal is stuck. It's not to address incidents where people have their foot partially and barely on the brake (which as others point out is a common occurrence older people with little consequence other than brake lights continuously being illuminated)!

I have seen zero indication that fatal accidents that have occurred are because people have their foot on both pedals. It is because the accelerator pedal is stuck or because they have their foot fully on the accelerator pedal. And even if they have their foot on both, they would have it floored, in which case the brake would overwhelm the available torque.
If there are use cases for setting up launch control and hill hold, fine, allow that scenario to proceed, likely to say 10mph, on a hill start. But once that has concluded, don't allow the car to continue accelerating off. You're not still hill starting at 60mph. If you've got both pedals pressed, even slightly, at street speeds then warn and cut the motor power enough to actually slow the car. Otherwise what is the point of the safety system if it doesn't slow a speeding car?
Doing something like that adds the complexity you were criticizing previously. The action should be consistent, just like it is in a normal vehicle and a max torque limit accomplishes that. Adding speed based variables adds additional complexity that increases chances of failure in an incident.

Again you are missing the point of the system: the goal is to allow the brake override the accelerator when it gets stuck. It is not to have the brake prevent accelerator application.