Toyota UA-LAC

[Huw Powell]

I agree that a software flaw/glitch/bug could be a big factor here.

These cars aren't like my 80s Audis or my 70s truck, pretty much every 
"feature" is mediated by a/the computer, right?

- the throttle is controlled by a computer, not a cable
- the brakes are run by a computer, not your foot pressing on a column 
of fluid
- the transmission isn't just a bunch of gears one can disengage with a 
  lever

etc. etc.

Some random thoughts - trying to brake at WOT and high speed with a 
full-on ABS/traction control system might result in inability to brake 
as hard as possible (each time the ABS pulls pressure off the pads, 
aren't they now "dragging" for a moment?).

It might not be possible to put tranny into neutral at speed.

It might not be possible, even, to turn off the engine with the car 
moving for safety reasons (you'd be turning off everything else with it).

And lastly, just for fun, braking against 200hp at the wheels (a 
reasonable figure these days) generates about 37,000 watts (50 * 750) of 
energy at each brake (more at front, less at rear).  That's a *lot* of 
heat.  Although my assumption that all the engine hp have to be 
converted as fast as they are made might be wrong ;)

Ed Kellock wrote:
> In addition to the 3-second press to turn off the ignition being maybe too
> much for some drivers to manage in such a crisis situation, if indeed there
> is a software issue, then the 3-second turnoff operation might also be
> ineffective.
> 
> Ed
> 
> 
> Unfortunately, some of the car in question also have the "smart key" system
> in them, in which a button is used for shutdown. Unfortunately, it has to be
> held in for 3 seconds to work, which is an eternity when in this situation.
> 
> I'll agree with John on this one, I think it's a software problem. I've
> though this since learning about the problem and looking at my wife's car.
> There is no such issue with my wife's 05 camry 4-cyl, which is throttled by
> a cable. But, these cars in question are throttle by wire, and I think just
> the right circumstances bring out a bug that holds the throttle wide open.
> 
> Just my .02,
> Tony


> .  As for the sticking throttle, I firmly believe,
>>> and never surface in the media, that they have a massive (and VERY
>>> scary) software problem, compounded by Toyota's "taking a chance" by 
>>> choosing to forgo the "failsafe" used by European manufacturers.  

-- 
Huw Powell

http://www.humanspeakers.com/audi

http://www.humanthoughts.org/