Automotive failures

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Might be a FPGA of which I'm not knowledgable. Can one reconstruct VHDL (or whatever) from a chip?

C: i = "told you so";

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FPGA configuration is usually done from a flash memory chip. although there are some FPGAs that have on-chip flash. It's virtually impossible to reverse-compile FPGA configuration files.

Leon Heller G1HSM

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Here is a report by Prof. Gilbert describing some of his experiments regarding fault detection by the ECM which unfortunately didn't appear to be identified:

http://www.safetyresearch.net/Li...

C: i = "told you so";

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bobgardner wrote:
News says Toyota owners with gas pedal mod installed are still getting runaway. Anybody know what cpu is in a toyota engine comtroller? If some guy with a little time on his hands could go to the junkyard and get a toyota computer and post the hex dump, a bunch of us geeks could start disassembling subroutines and submitting them to a cvs, and when we get it to compile and be about the same, by then we'll know about what every subroutine does, and someone will see a problem. Edmunds has offered $1 million bux for whoever solves the problem.

My idea would be to lay it out on a bench and play voltage waveforms into the pot inputs and observe the throttle position motor voltages and plot those so you can see the anomalies. Mu guess it you can get evidence of a software failure under the right conditions. Great Fun! Of course it could also have something to do with mass air flow sensors, etc.

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My idea was to get it in the shop idling, and strike an arc with welding rods in various locations near the engine computer, simulating strong rf noise interference. If the engine sputtered, one might guess it was being reset and recovering in 50-100ms with nothing more that a stutter. Of course if it came back at full throttle, you would be a millionaire.

Imagecraft compiler user

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That's not a really scientific way to find errors, you still don't know what the design flaw is.

In the Toyota system the throttle pedal sensor consists of two linear hall sensors, and the secondary sensor output X volts more then the primary sensor. The firmware does not have robust enough plausibility checks on these two voltages. Other makes use a sensor that has a different slope on the secondary output; on some the secondary sensor outputs the inverse of the primary one. I think they should have choosen for a frequency output, like Ford MAP sensors do, not analogue voltages.

And another major strategy flaw is not to return the engine to idle when the brake pedal is pressed. I guess Toyota wanted to serve the people who like to do burnouts :)

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jayjay1974 wrote:
And another major strategy flaw is not to return the engine to idle when the brake pedal is pressed. I guess Toyota wanted to serve the people who like to do burnouts :)

I'm not sure that is a flaw; it's a design decision that maintains the original operating paradigm. The accelerator pedal controls the speed of the engine. The brake controls the speed of the car.

Also, I can see situations where you might, for example, catch the edge of the brake pedal if a bit clumsy when shifting back to the accelerator; it'd be embarrassing if the engine cut back as you did it.

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I meant that applied brakes with fully applied throttle is not a normal situation; except for very experienced rally and race drivers that master heel and toe.

The protection does not have to kick in immediately, but only after when it persists longer than a second or so.

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That scenario could be monitored by a completely autonomous system consisting of a separate brake pedal switch and a separate engine speed sensor, and a kill relay or something more sophisticated.

Imagecraft compiler user

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On the anti-lock breaks: Swedish road authority investigates every accident where life is lost (and a lot of other accidents). I have no har evidense/link right now, so going from memory on this. The road authority can see changes in type, frequency etc of car accidents correlate (or not) with different safety measures implemented in cars. They expected to see "curves being bent" with the introduction of anti-lock breaks, but the effects where small (none?). For anti-skid (correct term?) however, the effects where readily detectable.

I have had my theory on why it came out this way:

Anti-lock breaks has a demand on the driver. He has to interact correctly with the system. Before anti-lock the emergency "break and avoid" manouvre was break hard (but try to avoid lock-up), release break, steer, break again... - repeat. With anti-lock breaks you need to learn a completely different technique. Breaks as hard as you can. Never mind the noise - it is an indicator of the system working. At the same time steer clear of the hazard.

Anti-skid makes no demand on the driver. It will engage autonomously when a skid condition is detected.

We should have more of those systems made mandatory. Systems that help maintain distance to the vehicle in front. Systems that help make lane-changes safe. Systems that help detect wild game ahead. Systems that help detect driver fatigue. Etc etc.

And yes, I suffer from the same thing that Smiley does. My semi-serious fear of flying makes it a force-of-will thing to get on the plane, but I happily drive to the airport. Totally irrational.

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"Some questions have no answers."[C Baird] "There comes a point where the spoon-feeding has to stop and the independent thinking has to start." [C Lawson] "There are always ways to disagree, without being disagreeable."[E Weddington] "Words represent concepts. Use the wrong words, communicate the wrong concept." [J Morin] "Persistence only goes so far if you set yourself up for failure." [Kartman]

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jayjay1974 wrote:
...In the Toyota system the throttle pedal sensor consists of two linear hall sensors, ...

Since its a system that relies on magnetic fields i wonder if the incidents have a connection to teh drivers footwear, ie. steel toes or girls boots with all sorts of large metal buckles.

Again, just an idea. If it is a magnetic interference problem with steel toe footwear, a welders steel toes could become magnetized if their feet are always kicking around their cables while welding.

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It seems to be the Toyota problem is only in certain markets. They might use different engine controls in certain markets due to import restrictions etc. If that is the case, then that may point the finger.

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IIRC A lot of Toyota's got recalled in NL too. And in NL stick shift is still dominant. Manual transmissions have one big advantage over autoboxes... you can kill the mechanical link at any time by just pressing the left pedal :)

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Do all the cars that exhibit rogue acceleration have cruise control? Was it 'on' but disengaged when incident occurred? Did the loose nut behind the wheel hit the 'resume' button when fumbling for his cell phone?

Imagecraft compiler user

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Finally found a bit of info on the ECM:

Quote:
The two engine control modules use a common Toyota-branded NEC µPD70F3155 32-bit microprocessor as the primary source of computing power. Neither the ECM nor the HVECU contain discrete memory components; the NEC processor die contains both the volatile working memory and the nonvolatile ROM used to store control code.

From: http://www.techonline.com/produc...

C: i = "told you so";

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Yesterday in California a Prius went out of control full throttle and the driver got the highway patrol to help him get it stopped after reaching speeds over 90 mph.
They had to do it on an uphill grade, full parking and foot brakes and turn off engine+ patrol cruisser in front of the Toyota to get it stopped. Driver said he had tried to get dealer to do the recall as he had a card in the mail.. dealer said nope, your not on our list to do anything.

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In a car with an automatic trans, you just shift into neutral. In a prius, is there a shift lever with fwd neutral and reverse? How do you tell it to back up? (Concentrate real hard and it reads your brain waves...)

Imagecraft compiler user

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I dont know but the drive said the brakes smelled like they were cooking when he was on the cell phone with the cops.

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Then they overheated and then they stop working (fading). I always assumed the brakes are easily able to overpower the engine. I almost want to try it out myself right now.

Why did the driver not simply turn off the ignition? Likely he or she must have assumed that the brakes will stop working then; potentially fatal ignorance.

Or simply shift into neutral. Better to wreck the racing engine then to wreck yourself and your family and others.

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"After the car decelerated to about 50 mph, Sikes turned off the engine and coasted to a halt."

More:

"He feared turning the car off in the middle of traffic, expecting the steering wheel to lock. If he shifted into neutral, he worried that it would slip into reverse."

Sounds fishy to me.

C: i = "told you so";

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I have never driven a Prius but I think they have regenerative braking to convert eneregy back into the battery. Perhaps that does not work well with the key off? Does it have direct hydraulic brake action such as master cylinder to the wheel cylinder or is it all run by electronics? What ever it is the rotors probably are not up to heavy braking with wide open throttle.

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I saw that interview. I agree sounds fishy. Shifting to neutral with an auto or manual is the intelligent thing to do. The rev limiter will save the engine.

Local news suggested selecting park or neutral. Selecting park might fail the transmission.

I think many drivers have lost touch about what makes car go. That is a more serious condition than Toyota problems.

It all starts with a mental vision.

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Cant someone go look at their neighbor's prius and see if it has a shift lever with a neutral position?

Imagecraft compiler user

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Clearly the Prius does have a neutral position. See the quote above. The guy chose not to use it. You and I would probably have done that in about 5 seconds, right?

C: i = "told you so";

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Herewith the end result of years of teaching that technology - of any sort - is suitably for end users who *do not understand the concepts*.

Anyone who had thought about the possibility beforehand, or even looked at the key when he turned it to turn the car on, would have observed that there are almost invariably a number of positions of the key, of which the first is 'steering unlock' and the last 'start the engine' with usually two or three others between the two.

Turning the engine off does not lock the steering. Turning the engine off and leaving the clutch engaged does not kill either the power steering or the brakes - at least, in a manual car. I'm not sure what a slush-box does - but even so, both brakes and steering are mechanically connected and required to work in the absence of engine assistance, though the effort required may increase.

Really, this is a no-brainer: if the engine's running away with you, turn the bloody thing off.

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KitCarlson wrote:
I think many drivers have lost touch about what makes car go. That is a more serious condition than Toyota problems.

+a million

...and car manufacturers must know this, and are already doing things to tailor (promote vehicle ignorance) to it. For example some new cars don't even have temperature gauges but just a light that comes on when things are over heating.

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In the interview Sikes said he tried to shut it off, could not, then tried again. Very fishy. He also got back in the car to drive it on the flat bed.

By selecting neutral, and not shutting it off perhaps the fault could be proven and diagnosed.

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Brake fix and acceleration from Wiki

In February 2009, media reports revealed that over one hundred complaints had been made to the United States' National Highway Traffic Safety Administration's Office of Defects Investigation indicating that the MY 2010 Prius's brakes do not always function correctly. Two of the complaints were injury crashes,[65] and NHTSA launched an official investigation into the MY 2010 Prius brake system.[66] An internal NHTSA agency memo stated “It appears that when you hit a bump, the regenerative braking (front wheels only) cuts out, and there is a short delay until the friction braking kicks in. This results in loss of braking, which is experienced as acceleration (due to sudden end of deceleration from braking). Net impact is still a loss of braking/increase in stopping distance. This could be fatal for pedestrians — it happens when approaching stop lights if you hit a pothole.”.[67] Japan's Ministry of Transportation also ordered Toyota to investigate Prius braking problems after it had confirmed 14 complaints,[68] and Toyota said that it was aware of 77 Prius brake complaints in Japan.[69] At least one accident suspected of being linked to faulty braking on the Prius was reported in Japan in July 2009, when a Prius crashed head on into another car injuring two people.[70] The third generation Prius was recalled by Toyota because of problems in its brakes.[71]

In February 2010, Toyota said that it had fixed the braking problem on Prius models built since late January 2010 via a software change, and a forthcoming recall was reported for previously sold faulty Prius brake systems.[72][73] A major Toyota dealership in Tokyo said that Toyota had informed dealers that Prius brakes can sometimes fail to work for less than a second, but it had not told owners.[74][75] On February 9, 2010 Toyota announced a voluntary global recall of MY 2010 Prius models manufactured from the current model's introduction through late

January.[76] The recall entails a software fix for the ABS system, to improve brake response.[76] A total of 133,000 Prius vehicles in the U.S. and 52,000 in Europe are to receive the software update.[76] Guardian.co.uk reports that this affects the third-generation Prius built before 27 January 2010.

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My 1994 car's emissions computer had those fun loving Rubycon capacitors in it. Those fun loving caps end up with a hangover and puking their guts out all over the circuit.
About a $1 worth of new caps and a half hour of time can save a $600 ECU.

TheZuke!
dona nobis pacem

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Here we go:

Quote:
Sikes filed for bankruptcy in San Diego in 2008. According to documents, he was more than $700,000 in debt and roughly five months behind in payments on his Prius;
http://www.foxnews.com/story/0,2...

C: i = "told you so";

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Quote:
But the investigation of the vehicle, carried out jointly by safety officials from the National Highway Traffic Safety Administration and Toyota engineers, didn't find signs the brakes had been applied at full force at high speeds over a sustained period of time, the three people familiar with the investigation said.

The brakes were discolored and showed wear, but the pattern of friction suggested the driver had intermittently applied moderate pressure on the brakes, these people said, adding the investigation didn't find indicators of the heavy pressure described by Sikes.

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The ECUs are too complex. Too much firmware. Complex real time (managing too many things at once, including the fuel injection timing at sub-mSec levels), so there is bound to be race conditions and subtle bugs. I/O conditions that the firmware designer assumed couldn't happen. Not to mention CPU screw-ups due to simple memory read errors (the error rates ARE finite).

I watched Toyota's hour long video (on-line) about all their attempts to preclude EMI vulnerability, watchdog CPU, and so on. Nary a mention of how the assure the main ECU processor cannot have a firmware bug, and how the watchdog cannot fail to override the will of the main.

Gee, to turn off the ignition in these Hybrids and others, there's no power switch on the dash. Press and Hold the car's on/off button for 3 seconds and hope the firmware isn't stuck in a loop and ignoring you. Gee, in MACs and Windows, the soft-power-off fails once a week, eh?

I politely wrote about this to Toyota's feedback to the on-line seminar, addressing it to the VP who was in the seminar and gave out her email address. Response? Yes, you guessed right: none.

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NEWS FLASH: investigators overlaid the power grid maps with the run away Toyota problems... 39 accidents align with the grid passing over the roads and the one in California where 4 people died was a Lexus with an off duty highway patrol officer doing the driving. They were on the cell phone and the problem started after driving under a high line crossing the freeway.

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Mentioned by Moi, Feb 26... page 2 of this thread, 2nd message on the page.... last line mention EMI from search radar as possible source of interference. EMI from power lines might be similar Volts/meter at the engine controller?

Imagecraft compiler user

Last Edited: Thu. Apr 1, 2010 - 03:22 PM
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bobgardner wrote:
Mentioned by Moi, Feb 26... page 2 of this thread, 2nd message on the page.

Sorry Bob but I do not see what you are talking about. Your page two post does not mention the 39 failures that seem power grid related not did I see anything in it about the highway patrol driver. The story on the news this morning showed the national power grid and dots indicating how the accidents lined up. Further they said there was a passenger in the back seat of the Lexus who was talking to 91l while the highway patrol driver was trying to keep it under control at 110 MPH. The caller explained that their was some relation to their passing the high lines and the beginning of the run away throttle.

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Today's news says NASA is going to investigate the Toyota problems. These are the guys who had the Space Shuttle Challenger O ring problem, followed by tiles falling of another leading to a second failure.

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KnockKnock "Hi! We're from the Government and we're here to help!"

Imagecraft compiler user

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Also the guys who got us to the moon and back, as well as landing roving vehicles on Mars.

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X just traded her Kia for a Prius.

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