What you say is true if Toyota's system works as designed. If Toyota doesn't check the relationship between the two signals, then it becomes a lot easier, doesn't it?

Every company uses this two signal system (or more). If Gilbert is correct in saying it's much easier to fool Toyota's system than other makes and if what he is doing is something that could realistically (although rarely) happen, does it not make sense to investigate?

Rich A. Jensen:
2500 claims and I would guess that many of them (half or more) are bogus, they were cases of people putting their foot on the gas and thinking it's on the brake. Many of the claims are beyond plausible with people saying things like they put it in neutral and turned the car off and it kept accelerating.

But still, it doesn't matter how few there are. Other manufacturers have fewer incidences and without making their cars unprofitable to sell. So it isn't unreasonable to expect Toyota to do better and save some lives. Remember, you're talking about a company that omitted industry standard brake override. So it's difficult for me to say that Toyota cannot be wrong in how they designed their system. And I think you also probably aren't in a position to say they couldn't be wrong.

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Yes, I should've noted that many of those 2500 claims can probably be discounted.

Also, Gilbert noted during his testimony yesterday, that the two accelerator sensors are on the same chip and fed by the same power supply.

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I have no problems with more sane investigations, but rigged tests to contribute to hysteria benefit no one.

Remember 60 minutes and Audi? Did that get any closer to root cause?

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A rigged test is a necessary part of a sane investigation.

I'm a Ford fan. But I have no issue telling you that their cruise control override switch was an inexcusably poor design.

I will also tell you that having two sensors that are on the same chip, running off the same power supply, and returning almost the same value for throttle input is an incredibly poor design.

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With engineering, you engineer to the tests you perform, and you can reliably prevent only the failures that you anticipate.

Anecdotally, the Ford PowerStroke 6.0 injector issues were not discovered during testing because Ford used only a limited range of diesel fuels, and the injectors clogged when dirtier fuel was used than was used during testing (although the diesel fuel was still within legal limits).

It seems clear to me that Toyota's testing regimen for their throttle sensor is as flawed as Ford's testing regimen for their cruise control switch.

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Running off the same power supply is a non issue. Likewise with sensors on the same chip. Multi-sensor chips are the norm and are no less reliable than multichip design (unless the design can't detect chip failure). None of these are related to even this bogus recreation or anything else. Highlighting it is further smoke screen to alarm technologically illiterate public.

Of course introducing faults is valuable testing. But it is done methodically recording detailing conditions, and results.

Creating a fault condition, without detailing how it was done, then creating alarmist videos is nothing but yellow journalism.

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- Having two sensors on the same power supply, not a problem

- Having two sensors on the same chip, not a problem

- Having two sensors on the same chip fed by the same power supply generating nearly identical signals under normal operating conditions:

definitely a problem.

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Snowdog:
Just because 60 minutes and Audi was wrong doesn't mean this is wrong. You're making ridiculous assumptions there.

I'm sorry, I don't agree about the non-independent power supplies being a non-issue. If you are going to have two independent sensors, tying them together is a compromise and an issue.

If the signals are created with a resistive divider or PWM D/A, then changing the power supply level will change the output (sensor) signal too. So if both sensors are on a single power supply, then a glitch in that power supply will change both signals and by proportional amounts. This makes them less independent. The system would be more fail safe with independent power supplies.

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You could run different regulators for different output voltages and that could give a slight benefit on paper to protect you from a defect that isn't going to happen anyway. System robustness is a statistical game. You build the redundancies where they failure will realistically happen.

Competing designs at other auto companies are likely incredibly similar and have similar weaknesses. In hindsight none of them are going to be seen as perfect. But none of this brings us closer to root causes.

We should actually be examining "failure cars". A plane blows up and we find some pieces and figure out what happened.

In this case we apparently have no shortage of "failure cars". It should be a simple matter to examine them. If shorts are suspected, you can trace the wiring. Shorts aren't cause by magical gremlins. You need a physical failure of insulation or connectors. Anyone competent with time can find these, if they exist.

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"Competing designs at other auto companies are likely incredibly similar and have similar weaknesses. In hindsight none of them are going to be seen as perfect. But none of this brings us closer to root causes."

Under oath, yesterday, Gilbert said that every other vehicle that they performed this test on registered a DTC code and entered 'limp home' mode. He said this test was performed on other vehicles, and only the Toyota registered NO FAULT.

Statistical analysis suggests that something is amiss with Toyota's electronic throttle control---SUA complaints from Toyota outnumber all other manufacturers combined; and SUA complaints spiked after Toyota switched to electronic throttle control.

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"Competing designs at other auto companies are likely incredibly similar and have similar weaknesses. In hindsight none of them are going to be seen as perfect. But none of this brings us closer to root causes."

Under oath, yesterday, Gilbert said that every other vehicle that they performed this test on registered a DTC code and entered 'limp home' mode. He said this test was performed on other vehicles, and only the Toyota registered NO FAULT.

Statistical analysis suggests that something is amiss with Toyota's electronic throttle control---SUA complaints from Toyota outnumber all other manufacturers combined; and SUA complaints spiked after Toyota switched to electronic throttle control.

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I could design a test to fail for a Ford. Then perform that exact test on every other vehicle and it would pass.

If you design a test to fail on Toyota, of course it won't fool other cars computers.

Any time you work up a fake out for any system it will be unique to that system.

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Snowdog:
And if that fakeout you created for each system is a case that actually could reasonably happen, what's wrong with showing there is a fakeout that could happen?

You've stopped even bothering trying to deal with whether what he did could happen and just gone onto trying to treat this as a rerun of Dateline NBC. Well, you lumping the two together doesn't necessarily make it so.

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If you actually understand how things work, you should realize that you are given no details here to back up the alarmist video. You should also realize that once you understand how a system like this works, it will be relatively easy to game it.

I have ~15 years experience in HW/SW development which started writing low level micro controller code to sample sensor inputs and working hands on in labs testing the limits of the HW/SW combination to make them more robust.

All I see in this ABC demo is more yellow journalism.

We should be analyzing the cars that supposedly have issues. If they are shorts they should be detectable, if there are sticky accelerator, that should be detectable as well.

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