SUDDEN UNINTENDED ACCELERATION (SUA)

The Prius is fly by wire.
That means when you squash the accelerator pedal, you're only sending a request to the engine room for the squirrels to run a little faster on the treadmill.
When you engage the cruise, this request is merely originating from another source.

So....
The only three things that I see that are interesting with the data are: (1) brake was applied enough to engage the switch that lights the brake lights....
and (2) throttle position was constant.
This means that your wife is either a two-footed driver, something that I have no means of ascertaining, OR something like a purse, floor mat, pet cat, boat anchor, President's missing tax returns or maybe just gravity was holding the throttle at a constant .78 meaning what, exactly?
.78 percent?
78 percent of full throttle?
76 Trombones with 2 spares?
.78 Pirate Ninjas?
That's an important piece of data that's missing from my picture of this incident....

I also see that (3) the engine was just a little above idle...at 1400 rpm.
Definitely NOT enough to overwhelm the brakes, given the Priuses non-tractor-like torque.
Even a 700+BHP Dodge Challenger Hellcat driven by an adolescent teenage male driver will stay in one place with the engine howling like a wounded banshee......if the brakes are applied correctly.

It's a lawyer thing.
They do it that way on purpose.

Unknown (by me) are:
1. Driver's blood chemistry, experience, driving habits, driving history.
2. Terrain and environment.
3. How many items were in the people compartment of the car, particularly on the floor, in front of the driver's seat.

If I'm Toyota's lawyers......and they HAVE lawyers.....I'm calling this cockpit error, and telling the dealer to do exactly what they're doing which is wait for the customer to lawyer up.
There IS NO WAY to prove one way or another what happened, and Yota has no little amount of experience fighting SUA claims.

Negotiate, litigate, or liquidate.

Your call.

Good Luck!

 

please see post #30

 

really?

 

Modifying brake pedal for left foot braking | PriusChat

OOOOooooo!
I'm sure THAT's not going to come out in court.....

 

14V is the HV -> 12V inverter output, not the resting or starting battery voltage.

 

Another theoretical possibility is a dead firmware task, as ChapmanF mentions back at post #89. This is a type of possible design defect we really need to root out, but is scarce enough to be lost in a larger flood of driver errors.

Another thing to be reviewed is whether the EDR's recorded time window fits the actual runaway event, or is it just the last 5 seconds before the car was manually shut off but too late to see the primary incident. Without a hard collision to deploy airbags, the data we really want to see might have expired and been overwritten by new data. That is an inherent problem with short data buffers.

 

we'll never know.

i'm just glad that in almost 20 years of driving toyotas, my software has never reached critical mass

 

I lean away from that as a possibility because of the "science" of statistics.

yeah....
People DO win lotteries, get hit by lightning, or practice common courtesy when they talk politics - but these are exceedingly rare things, and even IF Occam didn't shave here, there's a little thing called 'burden of proof' that's even more applicable in civil hearings.
If I'm on the jury.....this is cockpit error....and I say this as a person who swore an oath almost thirty years ago to NEVER EVER buy another Toyota product.

 

part of the problem that confuses the issue are the many false claims and remedies.

1) floor mats wee not secured - never was an issue

2) throttle pedal was too long - never was an issue

3) throttle made in indiana was an issue - unknown if it ever caused u/a

4) right after the chp accident, all kind of people started claiming it happened to them - some maybe true, some maybe not

5) a person was caught dead red, claiming he couldn't stop his car, but was lying, hoping to cash in

6) nasa claimed they could find nothing wrong with the software

7) there are probably other red flags, which have clouded the discovery process and actual code repair

 

Yes, for any single randomly selected incident, this possibility is statistically unlikely. We already have previous studies very strongly suggesting that more than 80% of these are operator error. But a few other causes keep popping up infrequently and demonstrating that pilot errors don't cover 100%.

This forum has received numerous reports of SUAs over the years. Not unusually high compared the fairly common similar incidents (with actual damage) in my region in a very wide variety of other passenger cars, but high enough to include one or a few non-operator-induced cases if such exist. And reviews haven't given high confidence in firmware quality. Our knowledge suggests that there are many more rare but real machine defects still hiding out.

I don't want to be one to browbeat an actual defect victim with public accusations that it was just their own mistake, even when that accurately describes most such cases. I have zero confidence that it covers all of them. And there is great value to capturing and identifying the actual defects, even when it will be difficult and expensive to do so.

 

if you hang around here, you will see the recall threads, and the link to the california dealer who refuses to sell the defective deadly prius and is suing toyota.

however, this has nothing to do with sua.

 

wouldn't surprise me in the least. have before, and will again. as soon as the lawyers see enough blood to make it worthwhile.

 

This was reported in Prius Chat two months ago. I caught it in normal daily news before logging in here. My notification from Toyota arrived in the mail sometime last month while I was away.

Samples:
RECALL - USA TODAY, WSJ | PriusChat
Prius Recall - October 2018 | PriusChat
Recall in the news | PriusChat
New Recall | PriusChat

 

That was my understanding as well. Caveat, I'm not an expert. It's just internet understanding.
But I have always heard it referred to as Drive by Wire. Which is confusing because it actually means the opposite. As yes the accelerator pedal actually acts as a input of computer controlled request. There is no direct "wire" or pedal to throttle connection.

So in my mind, that means hypothetically you could have a flaw in the accelerator system, and the physical position of the accelerator pedal could be totally immaterial. If there was a miscommunication of requested input for acceleration or translation of that requested input.

Of course, all automakers claim their software and the system is incapable of suffering this malady.

But at least tangibly, Drive by Wire, is computer input request.
This is the situation with nearly all modern vehicles.

I think of it, kind of like the Prius "shift" knob dongle. While it kind of looks like a traditional shift knob situation, it actual also is a computer controlled request. You are not really shifting anything when moving it, you are telling the Prius you wish to select your choice.

However, I think this really has little to do with the OP's immediate situation.

I said way back in post #20....

" By this description, ( The OP's original description of events ) speculatively it would seem to me, this would be saying you had at least 2 systems failing simultaneously. You would have to have the vehicle accelerating spontaneously, so a failure of the drive by wire system-fuel delivery, acceleration, AND a failure of the braking system. "-post #20

IMO this truth in any type of litigation or court situation works in favor of Toyota.

Basically Toyota would be able to point to Black Box data, supporting the idea that it was operator error, coupled with the fact the OP did modify the brake pedal, which may mean nothing in reality, but in court would place the shadow of doubt in regards to it NOT being OEM. The OP would be trying to prove not just one vehicle system failed but at least two...accelerator and brakes.
And it would become "evidence"-information retrieved and analyzed by Toyota from the black box vs. perception of what happened by Driver and Passenger. In my personal opinion, in the seat perception of the experience loses here. That's just personal opinion, not played out or tested fact.

I'm also going to go way back to the start of this thread and ask, as was stated and asked early...
Did the OP file a complaint with the NHTSA?

One person, one couple, with one personal incident, is a situation that is a huge challenge for anyone litigating against Toyota.

BUT...

File a complaint, and if over a period of time, a trend can be identified, that changes the equation.
That's not immediate or even probably satisfying resolution for the OP, but it might be the best thing they could do.

In the mean time...whatever the reality I commiserate with the OP.
Whatever actually happened? And I CAN'T really KNOW what actually happened,
If you lose faith in the safety of the machine? That's a tough situation.

 

It should also be noted that the separate braking system is not completely Drive-By-Wire. Yes, the power assist / stroke simulator layer is entirely by-wire. But in accordance with NHTSA passenger car requirements, it has a fail-safe path to entirely manual braking when that power assist system fails -- JUST STOMP REALLY HARD ON THE BRAKE PEDAL!

All that brake-by-wire power assist is truly a layer between the driver's foot and the underlying hydraulic-mechanical system. If something goes wrong with that power-electronic-boost layer, then just squash it with pure brute force, pressing right through it. In other words, brake just like in the old days before Power Brakes -- by stomping hard with all your body weight. The NHTSA regulations define just how much braking ability must be present when pressing with a pedal force of 500 newtons (metric for 112.4 pounds). While it isn't nearly as good as with functioning power brakes, it is usable for emergency purposes.

 

True...but I was talking about Drive by Wire...accelerator..not brake pedal. As you say..and I said, the brakes are a separate system.
I concede actually with both systems, I'm not an engineer, and my understanding of how they work is culled from what I learn at sites like Prus Chat and other automotive sites.
No degree in "Drive by Wire" systems.
Any litigation or defense would require a much greater understanding of the system(s) as a whole than I can provide.

But in my comments, while I recognize the OP is talking about a failure of at least TWO separate systems, my commentary about drive by wire, was focused on the accelerator, not the brakes.