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Location: Sitting inside a TV truck, Somewhere, more then likely in the Southeastern region, United States

I am a grouchy, bald headed old fart filled with opinions and not the least bit shy about sharing them.

Wednesday, March 10, 2010

We got the Toyota PR blues!

Today brought a couple things on the Toyota front. The first item on the Toyota uncommanded acceleration news front is Yesterday's rather harrowing ride down California's I-8 in yet another runaway Toyota. According to multiple news reports, this one required help from the California State Patrol to get the car stopped. Why the driver didn't drop the car into neutral, I'll never know.

The second was an opportunity to watch Toyota's live press conference and webcast. That was some interesting TV. Anyone watching learned the basics of Toyota's fly-by-wire throttle control system. At least the part of it that involves human input.

However the main focus of the presentation is an attempt to shoot down an experiment by Professor David Gilbert. Gilbert demonstrated that under a fairly narrow set of specific circumstances an uncommanded acceleration can take place.  A pedal-to-the-metal acceleration that occurs without setting a fault code in the computer or generating a "failsafe" shut down. In fact 90% of this presentation was all about smacking Gilbert across the nose with a rolled up news paper.

Toyota's presentation emphasized to a fault that Professor David Gilbert "re-engineered" the circuit. That he rewired the harness to introduce that fault condition.

That he did.

Toyota engineers and spokespeople stressed many times that trial lawyers suing Toyota are paying Gilbert to discover and perform that trick.

That they are.

Everyone at Toyota repeated many times, even while giving us a live demonstration of Gilbert's magic trick, the conditions that Gilbert set up creating a faultless unintended acceleration required, at the least, a wild combination of cascading events in the correct sequence.

They are right.

But Gilbert did demonstrate in an easily reproducible manner that it is possible to get an uncommanded full throttle acceleration while the computer thinks everything is just dandy. Something that Toyota said could not occur under any circumstances until Gilbert did his resistor trick.

There were some things missing from the Toyota presentation. It would have been interesting to see the computer module itself and the position of those wires in the computer connector. A look at the insides of one of those computer modules to follow the traces from the dual throttle sending wires would be enlightening to electron pushers like myself.

Even more interesting would be to look at the part no one seems to be talking about. That is the driver circuitry and electromechanical linkage that opens and closes the butterfly valve at the engine air intake. Some discussion as to how the computer knows where the butterfly is positioned would have been interesting.

Roughly two minutes were dedicated to praising the software that runs the computer that runs the car. But nothing was said about any code that gives the brake absolute override over the rest of the system. There is something that common sense says should be in every fly-by-wire ground vehicle.

It is a given that that Toyota engineers are looking at all of this and things I haven't even dreamed of. There are far wiser people then myself putting in some long hours on this problem right now as you read this. Toyota wants the problem indentified and fixed. This is as it should be. But if yesterday's Prius event turns out to be the real deal, Toyota has even more serious problems then they thought.

Doing the PR version of dropping a safe on Gilbert's head isn't going to fix it.


I hooked up my accelerator pedal in my car to my brake lights. I hit the gas, people behind me stop, and I'm gone.
Steven Wright

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