Prius locks up like a frozen PC

[bwilson4web]

Originally Posted by web1b

. . .
Check all the comments sections on news sites and Youtube etc. on all the stories about the Sikes incident. . . .

Thanks to Google, I just got back from reading the whole of the Internet and found only one such claim:

"The Prius is controlled by computers because it is drive by wire and when the ECU locks up, it ignores your inputs from the starter button, brake, gear selector and gas pedal."

We are hoping the author may someday provide credible sources for this quote. One excellent source would be the many posts in PriusChat by the friendly folks at PriusChat who own, drive, and work on their Prius. They have been trying to share their extensive experience and hands-on knowledge with the author.

As gentle as possible, we are trying to inform the author that we know how our Prius work and are not concerned. This includes many of us who recently got a software update to our skid control ECU and now find that our Prius works better. We are not afraid of computers ... like the one being used to read this message.

Computers work both ways and often include a log showing how the driver has been operating the car. Sikes may have been surprised to learn that his Prius had a record showing 250 operations of the brake pedal and accelerator. That goes right along with his admission that he ignored the recorded, 911 operator advice to shift into "neutral" or "turn off the car."

Computers have provided direct evidence, which Sikes chose to ignore, that showed:

• he called 911 to ask for help
• the 911 operator gave him the right advice
• he ignored the advice of the 911 operator
• a highway patrol officer had to overtake him at high speed
• while driving at high speed, the officer gave Sikes the 911 operator advice
• then and only then did Sikes follow the advice
• the car came to a stop

We suspect that upon learning the Prius records the operator inputs, there will be a sudden reduction in the number of Prius complaints claiming the car 'ran away.'

Bob Wilson

[web1b]

Originally Posted by bwilson4web

Thanks to Google, I just got back from reading the whole of the Internet and found only one such claim:
We are hoping the author may someday provide credible sources for this quote. In the meanwhile, the friendly folks at PriusChat who own, drive, and work on their Prius have been trying to share our extensive experience and hands-on knowledge with the author.

Bob Wilson

Wow, you didn't look very hard. It took longer to copy and paste these comments than to find them and there are just afew of thousands of similar opinions.

How the brakes on a Prius work – The Blogs at HowStuffWorks

The Prius is unique because it is one of the few cars to have “brake by wire”. When you push on the brake pedal, there is no direct connection to the actual brake pads the wheels. Instead, the pedal sends a signal to a computer, which decides whether the to activate the regenerative braking system, the actual disk brakes, or both. Because there is a computer in the middle, software problems can cause the brakes to work in bizarre ways. This article explains the situation:

Runaway Prius driver: Brakes were almost burned | Product Design and Development

• 
  
• 
  trunner 3/10/2010 2:45:10 PM
  Gas-by-wire, brake-by-wire, all running through a computer system that is also trying to manage ABS, maximize mileage, and minimize emissions. What could go wrong? Too complex, too many contradictory conditions, too many unnecessary features. There will never be enough time to fully analyze such a system. In a corporate world motivated by Time-to-Market and feuled by hubris, we get this mess.
  
  
• 
  Ram 3/10/2010 1:06:30 PM
  The Prius does not have a key, it has a Power on/off button. Turning off the power button turns off many of the systems including the power steering. The shift lever is connected by hall sensors. The brake pads are only engaged below 5 mph until which time regenerative braking charges the batteries. Everything is "fly-by wire" in the Prius.
  

“I am not afraid of my Toyota Prius”

tizona 03.12.10 at 10:56 am A Toyota Prius is a fly-by-wire design. You can only switch into neutral if that request is acknowledged by a computer. The “gear shifter” is a simple joystick control not too much different from a video game controller. Any computer system can fail or get hung up. If a Prius computer system does hang, there is no kill switch in the cockpit that provides for a direct, mechanical disconnect of all computer control to force the thing to shut down. I just hope the things don’t leverage microsoft sotware in their OS. You can’t pull the battery out of a Prius at 90 MPH on 101.

YouTube - Broadcast Yourself.

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Sure it works when the car is operating normally, but if there's some sort of electrical or computer malfunction, the shift-by-wire interface may be disrupted.

It could be the same fault that causes the electronic throttle to fly open.

[dogfriend]

If you have decided that comments from random strangers on YouTube are a valid research source, then I say:

Good luck with all that.

[2k1Toaster]

One thing you fail to realize is that the ECUs have failsafe watchdogs. If code isnt updated before a timer runs out (usually every so many microseconds or sooner), then it throws an error and resets. If an ECU does freeze, it will just cycle on and off, create a log on the next startup, and work just fine faster than you can blink an eye, literally.

[web1b]

Originally Posted by dogfriend

If you have decided that comments from random strangers on YouTube are a valid research source, then I say:

Good luck with all that.

I didn't say they were correct, but that's what the opinions are out there.

[bwilson4web]

Originally Posted by web1b

Wow, you didn't look very hard. . . .

That is the beauty of computers, we don't have to look very hard. Thanks for taking your own advice but the original "quote" was found in only one place and from just one author.

More to the point, we are happy that our cars are computer controlled. The recent software update to the skid control ECU improves operation at speeds under 19 mph, in the rain or slippery conditions, running over a speed bump or pot hole, and holding the brake at a constant setting. Half of the Prius owners hadn't even experience or recognized there was a problem. Only one in five thought it was a severe problem easily handled by just pushing the brake pedal harder.

The point is Sikes called 911 for help and choose by his own admission to ignore what he was told to do. It took a highway patrol officer running at high speed, parallel to him, shouting the same instructions, 20 minutes later, that Sikes finally followed the advice and stopped the car. Meanwhile, the car computers recorded 250 braking and accelerator operations. Sikes got caught.

Bob Wilson

[fuzzy1]

Originally Posted by JamesBurke

... I am not aware of a single proven case of sudden or unintended acceleration having taken place in any vehicle do to mechanical or electrical reasons. Ever! ...

[emphasis added]

You aren't serious about the 'mechanical' part of this claim, are you?

No throttle icing (current Aveo investigation), no broken motor mounts yanking on throttle cable (past recall), no broken springs, no disconnected vacuum hoses, etc.?

There was a very good reason why, a couple generations ago, most drivers knew what to do when unintended acceleration occurred.

[a1a1a1]

Originally Posted by bwilson4web

That is the beauty of computers, we don't have to look very hard. Thanks for taking your own advice but the original "quote" was found in only one place and from just one author.

Here's a good article to read from the Institute of Electrical and Electronics Engineer (IEEE): IEEE Spectrum: Toyota's Sudden Unintended Acceleration Remedy Doesn't Convince Everyone

And, here are a few quotes from the comments section:

I am a physicist, retired after 20 years working at the Jet Propulsion Laboratory and other research labs before that. I have been following the Los Angeles Times articles about the sudden acceleration problems in Toyota and other vehicles. As a recent article has stated, a number of people are thinking that the problem is in the electronics. I do too.

(By a Ph.D. from a major government research lab run by one of the world's leading technical universities.)

UA can have many sources, and all components can fail or be badly designed. However, Toyota's behavior here has been inexcusable. It's becoming obvious that they knew there was a problem, tried to minimize it, tried to blame someone else, still aren't confessing fully, and have a corporate culture that resembles the old and ugly GM, not the great post-war company that Dr. Toyoda built. NHTSA is also to blame, but the contributory percentage is something like .1%. Electronic component failures are particularly pernicious because the pattern is harder to find, harder to fix, and harder to explain.

(By another Ph.D. famous for developing a computer language and whose academic story Obama wrote about in Dreams From My Father.)

The IEEE blogs are a treasure trove of commentary and technical analyses, not necessarily Toyota focused. I recommend a reading of these intellectual leaders' comments for a solid technical foundation on the issues being addressed.

[bwilson4web]

Originally Posted by a1a1a1

. . . I recommend a reading of these intellectual leaders' comments for a solid technical foundation on the issues being addressed.

I recommend bringing facts and data, some reproducible symptom or circuit analysis or other empirical data demonstrating a fault or flaw. A hypothesis is not a diagnosis but just another guess until empirical data is brought forth.

If you have a Prius, grab your instruments, head out to the driveway and at least pull a Gilbert ... do the hard work and find the fault. If you don't want to use your primary ride, buy a second one and experiment with that one. There are more than a few of us who do experiment.

Speculation, sharing Fear Uncertainty and Doubt (FUD), these soon become "the boy who cried wolf" and not worth the time I just spent explaining the basis of all modern science and technology ... empiricism.

Bob Wilson

[JimboPalmer]

Originally Posted by JamesBurke

I am not aware of a single proven case of sudden or unintended acceleration having taken place in any vehicle do to mechanical or electrical reasons. Ever!.

I was a passenger in a Ford Aerostar in which the throttle cable became fouled with the hood release, when the driver pressed the pedal, the hood came up, and draggged the throttle cable with it. It is interesting being at full throttle with the hood up. I 'navigated' out the window.

We hit the brakes, and stopped the van, then put it in park and shut it off. Ty-wraps on the cables, prevented re-occurrence.