OT Toyota's Problem OT

[pflaming]

Got this question from a friend. Observation: Garage openers at one time would open when an airplane went overhead and sent a stray signal. It is his understanding that the foot pedal 'communicates' with the engine via an electronic signal.

Question: Is it possible with all the electronic signals in the air, i.e., cell phones etc. that stray signals could 'foul up' the connection?

[JBNeal]

SHHHHH!!! We're not supposed to know this yet.

[48Dodger]

Modern Automobiles use a ETC (eletronic throttle control) or TPS (throttle position sensor)which is/are closed circuts to the ECU (electronic conrtol unit). RF waves (TV remote or gargae opener) are not used to run the electric motors that do the actual work of opening and closing the throttle. Redunant sensors and computer control, tie everything together with cruise control, traction control, etc..... they call it "drive by wire" or DbW. I'm sure its the gas pedal design. Its the only part that is still human controlled, or should I say, a "mechanically controlled system".

48D

[TodFitch]

Got this question from a friend. Observation: Garage openers at one time would open when an airplane went overhead and sent a stray signal. It is his understanding that the foot pedal 'communicates' with the engine via an electronic signal.

Question: Is it possible with all the electronic signals in the air, i.e., cell phones etc. that stray signals could 'foul up' the connection?

As another posted noted, the control electronics in is by wire, not wireless.

That said, wireless electronics have also come a long way. Barring nefarious actions, digitally encoded signals are pretty much on/off. That is the difference in signal to noise ratio between error free operation and no operation at all is pretty small. So it will "just work" until a certain level then it won't work at all. The odd intermittent behavior that old analog wireless systems like the old garage door openers had is much less frequent with current technology.

[John-T-53]

Toyota's problem is that they've gotten huge, (and that they're foreign).

When bloating happens, problems get harder to avoid and solve, and more people want to take from the company what they think they deserve. Just like Government Motors (GM).

[MBF]

I managed shop and personnel for a fleet of 500+ electric vehicles (material handling equipment) for many years. As the technology got more sophisticated-so did the troubleshooting processes and methods. I do know that when regenerative braking came on the scene, that one manufacturer was having all kinds of problems with cards and modules that would sometime cause the vehicle to act in the opposite manner (accellerating when stepping on the brake). Anytime you use an electric motor in a dual function (motive power, or regenerative braking-where the motor acts as a generator) the possibility exists that a stray input or a mixed input signal could cause an unexpected event. I think the discussion of a electronic whiskers in micro circuits now that the solder contains no lead is very interesting. Same thing w cold soldered assemblies. Time will tell, but give me a mechanical linkage w a cotterpin anyday. My 52 1 ton ran away last fall-and the gov't didn't have to do a recall or call out 1800 lawyers-pulled off the side of the road, put in a temporarty cotter pin-drove it home and made a permanent repair! Mike

[TodFitch]

...snip... My 52 1 ton ran away last fall-and the gov't didn't have to do a recall or call out 1800 lawyers-pulled off the side of the road, put in a temporarty cotter pin-drove it home and made a permanent repair! Mike

And I bet you knew how to put the vehicle into neutral and turn off the engine when it started racing.

I'm starting to hear counter reports on the news. Seems like the fellow in the San Diego area might have been trying a scam. And one in NY state has no indication that the brake pedal was used.

The one a while back where an off duty CHP officer and his family died is still the big mystery. That fellow should have known what to do, so it would seem something very strange happened. I know a couple of retired CHP officers and they are puzzled on that one too. Since we have two Priuses (a 2001 and a 2004) I have been following the reports with some interest.

[Plymouthy Adams]

Tin Whiskers.l..they are here..they are a serious problem in electronics...they can appear overnight it seems..I have cleared whiskers, cleaned and sealed circuits to try to prevent future problems...just because the technology is new, clean and more enviromentally friendly..does not prove it to be reliable..

[48Dodger]

I agree Tod. I've seen several reports saying "he got it down to 50 mph and then was able to put it in neutrel...." what? He wouldn't blow the motor in neutrel, not with rev limiters.....so what gives? I don't own a prius, but geeees, put it on N, hit the brakes and turn the key off. I'll take a blown motor over a crash anyday.......

http://www.guardian.co.uk/business/2010/mar/15/toyota-runaway-prius-not-feasible

"Toyota engineers also attended the investigation, and argued that the car's engine has a safety system that automatically cuts the engine power if both pedals are depressed at once."

"During his drive, Sikes was told by the emergency services to put the car into neutral, but declined, saying later that he was afraid this would cause it to "flip"."

Sounds like user error, or a Scam to me.

48D

[greg g]

Nothing like the whirr of an out of control electric motor to scare you sensless.

They probably also should check into that Neutral Flip Over Switch.

[austinsailor]

There is a good chance we'll never know the truth, even if they figure it out.

There are a number of aspects to this. As far as shutting it off, putting it in neutral, etc - most people wouldn't think it through at the panic time. A few years ago, there was a Ryder type truck that had the throttle stick. The woman burned up the brakes, someone else who figured out what was going on got in front, burned their brakes up trying to stop it, then she finally crashed. There was a big story on one of the major networks, they interviewed everyone, made a big story out of it, and never mentioned either shutting off the key, or putting it into neutral. What?? What an opportunity for a good community service announcement, they missed it. A trained guy, maybe. Average guy under pressure, even a cop? Probably not.

Even with that, and and me explaining it all to my wife, some time later the throttle stuck on our old Mercedes wagon. It never occurred to my wife to do it either.

The next problem is, all this info about what happened - like he alternated between the brakes and throttle 255 times. All this information is being reported by the very unit that we suspect may be bad. Talk about questionable sources. Like my Mercedes alternator that had a light to tell if it was charging. If it's broke, do you rely on it? and 255 times? That is just an 8 bit register that counts. An oscalation in the circuit could run the count up in microseconds. Do you really think a guy would alternate that many times in a minute even if he was trying to do a scam? Why would he? Doesn't make sense. He may have been trying a scam, but this evidence is pretty bogus.

And, the biggest thing is, electronics fail. I was on a project with Motorola that went on for a year or more. We'd have failures in a system that happened very rarely. The chip guys said it absolutely couldn't be caused by their chips, it had to be in our design that we used the chips in. After a year we were finally able to prove it was a fault in their manufacturing process causing a very infrequent failure under a very narrow set of circumstances. And we could repeat the test billions of times an hour in the lab, with a failure happening every day or two. How many times can you repeat the start, stop, acceleration sequence in a car? One car, might take a million years and you'd best have your test equipment set up right to catch it, or it'll be another million years. Then, you think they'd tell us, even if they found it? I doubt it. "Oh, there it is, guys, that glitch in the circuit we suspected. Let's tell everyone now, so we can pay out 100 gazillion dollars in damages."

I doubt you'll ever know.

[Plymouthy Adams]

I personally find all this a bit on the fishy side...like that runaway train with the roughe nuclear device loaded onboard..twas an isult I tell ya..an insult

[coW52Dodge]

Regardless of whether the system controls stuff by wires or not, it is possible that signals from transmitters get into the system and fool the system into doing something it isn't supposed to.

When you design something, you design it for minimal susceptibility to RF signals and, to make sure it indeed operates properly, most of the time you acceptance test the design. Especially mission critical equipment (military, medical, automotive) goes through rigorous testing.

That being said, if a signal is strong enough, close enough and just of the right frequency, it will get through and it will screw something up - but we're talking huge signals, stuff that likely makes lightbulbs light up without them being hooked up. Signals from cell phones are puny by comparison.

Long story short, you don't have a thing to worry about.

I do this stuff for a living.

[greg g]

I thought this through when considering to buy a new furnace for my house. Our current one is the original in a house that was built in 1960. So I asked the 4 guys who came about where their furnaces were made, they all Said the MAJOR Components were made in the USA. OK, howabout the fancy control boards for all the circuits and controls that come with today's furnaces. Blank looks, then answers of China or Mexico.

Now, please Chinese and Mexican members don't take offense but after reading reviews of the furnaces on the inter web, I found countless reports of failed circuit boards, and or other controls.

Verdict, keep old pilot light furnace, change the belt to quiet it down a bit, and leave well enough alone.

Electronic controls are great for precise measurments and "decision making", but I kinda like the old reliable stuff.

[Harvey Tank]

I got a recall on my 2010 Toyota camray. took it in to day it took them all day to do what ever they do. I still don't now what they did. like someone here said give me a linkage with a cottor pin or a peice of wire.

[greg g]

I have a older Ford Explorer as a use it once and a while utility and tow vehicle. It was subject to the Speed Controler Recall. I took it in they had it for a day, before I left, I opend the hood to look for evidence of any changes, new hardware shiner parts, disturbed underhood dirt, didn't see any thing, so I went in and asked to see the old parts that were removed. Was told since they did my vehicle early in the day, the parts went to the dumpster and it had been emptied during the day. On the way home I checked and all their dumpsters were full. I don't believe they did diddly, but since there was no cost involved, I guess i cant complain unless of course I become a victim of the fires caused by the failure. The paperwwork from the "service" is stored away form the vehicle just incase.

[MBF]

They might have just done a software update on your vehicle's ECM, or they could have just looked at it in the parking lot and said "looks good from here". One can only hope!

[br0k3N18]

why not ditch the electronic throttle and go back to cable operated? :think:

[TodFitch]

why not ditch the electronic throttle and go back to cable operated? :think:

Cables can stick too.

And on my Prius would that cable attach to the electric traction motor or the gasoline engine? Not sure how you control a electric motor with a cable other than running it into a sensor and then having some control electronics adjust the voltage/current/AC phase for the motor.

Basically anything you design and manufacture has a set of operational failures that can occur. Doesn't matter if it is hardware or software, you need to look at the whole thing as a system and think hard about what can go wrong and how you want the system to behave in response to every conceivable failure. Singly and in combination.

[Disturbed]

I have a older Ford Explorer as a use it once and a while utility and tow vehicle. It was subject to the Speed Controler Recall. I took it in they had it for a day, before I left, I opend the hood to look for evidence of any changes, new hardware shiner parts, disturbed underhood dirt, didn't see any thing, so I went in and asked to see the old parts that were removed. Was told since they did my vehicle early in the day, the parts went to the dumpster and it had been emptied during the day. On the way home I checked and all their dumpsters were full. I don't believe they did diddly, but since there was no cost involved, I guess i cant complain unless of course I become a victim of the fires caused by the failure. The paperwwork from the "service" is stored away form the vehicle just incase.

They changed a wire located under your Master cylinder ,the sensor leaks brake fluid and can cause a fire .

as far as the Toyota's are concerned I speculate that it is a software failure . They have so many safety's in place that if one part fails something else will check and keep things live all the time not to say that things can't go wrong but are unlikely

but if it is man made it will break no doubt about that !