I’m sure the FBI investigated the technical issues as well as the legal issues. I can’t imagine anyone looking into this issue while ignoring the technical aspects. That would only be half of an investigation.
“internal records showed that the automaker knew the problem was deepening”
Doesn’t this say that the problem was more than floor mats or operator error? They poo pooed it and changed floor mats but the problem was “deepening”. Chrysler said the same thing, and Audi did too and finally took the model off the line up.
In order for the investigation to determine “the automaker knew the problem was deepening,” they had to have investigated the technical nature of the problem itself. If there were no technical issues, what “problem” could they possibly be referring to?
A cosmic ray strike at the surface of the earth would be very rare indeed. There are systems with orders of magnitude higher risk (severity) and level of integration (probability) used on the surface of the earth that do not employ any radiation hardening in either hardware or software/firmware due to the effectiveness of the atmosphere. If this were plausible cause, it would be happening to other makes/models as well that are drive by wire.
The more likely cause is this:
“As well, the run-time stack of the real-time operating system was not large enough and that it was possible for the stack to grow large enough to overwrite data that could cause unintended acceleration.”
Stack overflow would be very plausible and probable cause. Back when this was first being discussed here I questioned the degree of scrutiny being applied to automotive firmware development…I’d love to see their V&V protocols…
Nope, the FBI didn’t have to investigate the technical side, the DOT (the appropriate, responsible agency for this) already had done so. That’s the other half to the government’s investigation. Had technical issues been part of the basis for the fine, I can’t imagine that being ignored in all the announcements.
I’m unaware of the FBI conducting a technical investigation of ANYTHING not law-enforcement related. Any you know of?
I agree with @texases. The FBI was investigating criminal activities related to the manner in which Toyota handled the unintended acceleration issue. The technical aspects were investigated by DoT and NASA (at DoT request). The $1.2-billion is jaw-dropping.
@jesmed, I agree that this is a complicated issue. It is interesting that you don’t think that GMs recall problems related to the ignition are complicated. I disagree with you on that issue.
Well whatever Twin Turbo was talking about with stack overflow (only understood about 20% of it), seems like that is far more complicated than an ignition switch that was turned too easily. I don’t know how you would correct a stack overflow problem or how to detect it after the fact. I would assume though it would require some analysis and additional computer power or something.
I have experienced unintended acceleration. Slowly coasting to a stop, I pushed on the brake and immediately sped up. I immediately pulled my foot up…it had been on the gas!!! Quickly onto the real brake and stopped fine. No harm, no foul. How could I have made such a boneheaded move? Ten years later, I can only plead “brain fart.” Whenever I read, “The more I pushed on the brake, the faster I went,” I know what happened.
I think jesmed may have said it best:
“In some cases, people just plain stepped on the wrong pedal
In some cases, the accelerator got stuck on the floor mats
In some cases, the accelerator pedal mechanism itself got stuck or returned abnormally
And in very rare cases, the car would accelerate on its own.”
Although, I’m not sure about the “very rare cases” part. They’re actually all very rare cases. So in categorizing the subset, they’re not necessarily. As for the study of the issue, if failure to find evidence for something was truly a basis for scientific decision-making, then a lot of celebrated science never would have gotten done. The failure to find something that you think might exist can never tell you that it doesn’t actually exist.
As for stepping on the wrong pedal, I have a really hard time with that. Once programmed the body is actually not such a bad machine. I’ve done a million miles or so, and have never hit the wrong pedal. I actually can’t even conceptualize my brain no knowing where my foot is in this set-up. It’s too hard-wired. And “panic” doesn’t explain that. That would have to happen after the misstep. So panic doesn’t explain why the misstep occurred in the first place. Though I guess people are all different, and some of them - I suppose - can forget how to ride a bike.
@cigroller, this article by a psychologist who studied the “wrong pedal” accidents has some interesting insights into how and why it happened in the Audi 5000:
Excerpts in quotations:
"In the cases that went to court, jurors naturally asked, why would a driver with decades of driving experience suddenly mistake the accelerator for the brake? And why would the episode last so long — often 6 to 10 seconds or more? Wouldn’t that be ample time to shut off the ignition, shift to neutral or engage the parking brake?
"First, in these situations, the driver does not really confuse the accelerator and the brake. Rather, the limbs do not do exactly what the brain tells them to. Noisy neuromuscular processes intervene to make the action slightly different from the one intended. The driver intends to press the brake, but once in a while these neuromuscular processes cause the foot to deviate from the intended trajectory — just as a basketball player who makes 90 percent of his free throws sometimes misses the hoop. This effect would be enhanced by the driver being slightly misaligned in the seat when he first gets in the car.
“The answer to the second question is that, when a car accelerates unexpectedly, the driver often panics, and just presses the brake harder and harder. Drivers typically do not shut off the ignition, shift to neutral or apply the parking brake.”
He also notes that after Audi implemented the “shift lock” that prevented shifting out of park unless the driver’s foot was on the brake, the unintended acceleration events practically disappeared…further evidence that people who crashed into garage doors had simply been pressing the wrong pedal when they first started the car up.
Interesting also that most of the Audi accidents were caused by older people who had little familiarity with the car they were driving. So these people were often not fully “programmed” on that particular car, as you put it, and perhaps beginning to lose some neuromuscular coordination.
I know of someone who had “unintended acceleration” in a non-Toyota car before the drive by wire systems were being used. She simply pushed the gas pedal and pushed harder, until she crashed the car. Fortunately nobody was hurt, it was a driver error.
We have a '05 Camry with the anchor hooks for the floor mats. I noticed last week that the carwash people felt they were a PITA and god rid of it and my wife did not notice. So I have to make a visit to the dealership.
@Bing
Consider this analogy. The stack is like counter space in your kitchen. When you bring groceries home, the counter is a temporary holding space for them. If you bring too much home it doesn’t all fit and maybe some overflows onto the kitchen table. In computers the counter is temporary data storage. Various things come and go but you try to keep it clean. The table is an area you keep for important variable storage (current gas pedal position). When the groceries overflow the counter, they displace what’s on the table. When the program comes along to read the data for gas pedal position, it gets erroneous information. This is oversimplified but just to explain what happens in stack overflow conditions.
There are a number of strategies to minimize the risk, verify it won’t happen and detect if it has, either at the time it is occurring, or through a post mortem investigation (if detection mechanisms employed). Any developer worth their salt has this stuff in place and the test protocols with results recorded.
Sorry formatting not working in this forum!! Why does this kind of thing get overlooked for so long here???
EDIT: logged in using Chrome browser on different computer and the formatting appears in the edit text box. Now will save and see if it shows up in the posted text…
@jesmed, thanks for posting that. I guess I’m going to have to just go with the random brain fart theory. It obviously happens. Luckily not as often as basketball players miss free throws.
“Unintended acceleration” has been around for decades. How do I know? I drove a tow truck in my later teenage years and I saw it from time to time. I pulled many vehicles from storefronts after the driver simply did not stop after reaching the parking spot in front of the store. The complaint was always the same…the harder I pushed the “brake”…the faster the vehicle went. All the cases that I was involved with were attributed to driver error. The only pattern that developed was the fact that most of the drivers were elderly.
The human mind is very complex…but very simple at times. Pushing the brake feels exactly like pushing the accelerator. Even if mechanical or electronic things go wrong…you can still shift to neutral or simply shut off the engine. The Toyota problem…for the most part… was caused by a sort of “mass hysteria” when the news broke that there was a problem with unintended acceleration.
I saw mass hysteria a few years ago at a company picnic. Someone announced that they got sick eating potato salad. As the information spread…people started getting sick all over the place…even though some of them had not even eaten the potato salad. The salad was checked by a lab and found to be perfectly normal. People were throwing up just the same. The human mind is a mysterious thing.
@missileman, interesting that your experience confirms most of the people who do this are elderly.
For me personally,
I’ve had the floor mat situation ( Never the wrong, or both pedals )
In my 92 Explorer I pulled out into 45mph traffic so I goosed it good to fit in the space without slowing anyone else.
Well , that action of pushing the pedal all the way down got the lower edge of the pedal caught on the leading edge of the mat and although I knew instantly what it was , it sure was quite a surprise and in traffic to boot !
So I put it in neutral and coasted…reached down and yanked the mat back…problem fixed.
I also know for a fact that someone’s occasional different shoes will cause them to press the pedals in a resultingly different manner…especially in the winter when the unfamilar boots come out for the season.
WET shoes slip off of the brake pedal too. an oddity people don’t analize as being their cause .
When my son was a teenager, he had the accelerator pedal stick on the 1978 Oldsmobile we owned. He was 50 miles from home, but had enough sense to put the car in neutral, coast off the highway, turn on the blinkers, turn off the engine and call a tow truck. I drove up to meet him. While the technician looked under the hood, my son figured out that the floor mat was holding down the pedal. He was embarrassed about calling for a tow and not seeing the problem. I complimented him on taking the safest action. I paid the tow bill even though he offered to pay it.
One advantage of the old days before power brakes and suspended pedals was that there was no way of hitting the accelerator and brake at the same time. The brake (and clutch if the car was a manual transmission) came out of the floorboard. You lifted your foot off the accelerator to step on the brake pedal. I suppose the disadvantage was that it did increase, by a fraction of a second, the time involved in lifting one’s foot rather than just sliding it over in an emergency stop.
Most cosmic rays (actually particles) are deflected by the earth’s magnetic field, hit some molecules in the atmosphere causing various reactions, or absorbed by shielding on earth. Most are protons and alpha particles and don’t have much energy, though with transistors and magnetic media getting so tiny cosmic rays do cause some errors. However, manufacturers are aware of this, know how to shield components and build in error correction. Electronics for use in the difficult environment of a car are usually a lot less vulnerable than a modern computer. The processors and other components they use are often very old designs that are less vulnerable to environmental effects. It’s certainly possible cosmic rays could have caused a few incidents, but not the numbers people were claiming.
Space is such a harsh place that even big, old electronics can have problems. No magnetic field or atmosphere subject spacecraft to lots of nasty radiation.
@jesmed…I don’t know if it’s a “confirmation” or not but the people, for the most part, were older citizens.
@MarkM…so the Roswell spacecraft could have crashed because of “old electronics?”
It is true older people are often unable to sense exactly where their feet are, as younger ones can. In fact, this is the best reason I know to teach people to drive with both feet on automatic transmissions. Moving those feet back and forth all day increases the probability a person will eventually make a mistake. it only takes once.
When I start my car, I verify carefully where my feet are, and then I am safe for the trip. (I am 71 which might be called older by some.)
Before someone wastes his time and mine claiming no one should drive with both feet, we had a cable guy tell us in NYC the cable company hired a consultant who told them to drive with both feet, to reduce reaction time which reduces wrecks.
I worked on high-tech stuff for over 30 years. I started embedded microprocessors in 1974. That first unit was a navigation computer for business jets. One day we got a call from a field service engineer asking me to check a certain sequence of events when approaching a waypoint. Sure enough, when you toggled a certain cockpit switch just before the waypoint, the nav computer would pretend it was switching course as programmed, but actually continued in the same straight line until somebody (hopefully) noticed before the crash. When I reported the customer complaint was verified, the company notified all customers to have maintenance disconnect that switch until we could supply new program cards.
I don’t know if Toyota uses microprocessors or another sort of computer called “Programmable Array Logic.” No one I know who knows about cars knows the difference, so I cannot get an answer.
But, I guarantee you if it uses a microprocessor, which means a software operated system, current state of the art for the military for several decades has included a circuit called WATCH DOG TIMER. That is a timer circuit which is connected to the RESTART function on the microprocessor.
If a defect in the program causes the computer to freeze in a program module, the timer does a forced reset on the microprocessor. The system has to be written to memory every so often so during restart, it knows exactly where to go again by looking in RAM.
A communications control box on a well known aircraft which under certain political conditions might carry atomic bombs over your house, heh, heh, had a problem and the watch dog timer was restarting the comm control box around 400 times a second.
No one noticed until I asked a senior lab tech what the period should be normally. He almost had cardiac arrest when I told him it was tripping every 2.5 milliseconds. The programmer did such a good job on the restart sequence no one had ever noticed until I actually looked at the output with a scope.
Still in at least one module, she forgot to put in the Reset Watch Dog timer loop and it got lost there. Or it froze somewhere.
I have wondered if that Toyota has a microprocessor based transmission and throttle control computer. If so, I would guess there is no watch dog timer. Or wasn’t until they paid out a billion bucks.
It it was a microprocessor based computer, it could switch the throttle to full speed ahead, then freeze up and be unable to shout it down again.
If PAL, I have no idea at all.
I do not wish to own a drive by wire car until I find out which type of computer it has.
Of course, since throttle on drive by wire is probably some sort of stepping motor, or servo like the idle Air Control system, there is also a possibility that the computer could switch the throttle servo to a higher setting, then lost connection to that servo which means it would be stuck at full throttle
I am another person who does not think they paid out over a billion dollars for carpet issues. It makes no sense. The government was pretty upset when they found out the real cause, and I don’t think they have told us what the real problem was.
The old people who drive with one foot may indeed have messed up. That HP guy who got killed did not reverse his feet to death.