My earlier post regarding the Saylor family Toyota crash may have sounded to some as if I was suspicious of a conspiracy or suicide as the root cause. Also, in light of recent news, a little clarification may help.
The "suspicious" part of this accident is how the expert driver managed to make the absolute worst choice in exiting the freeway at that point with an uncontrolled vehicle. That ramp sloped downward, to a busy "T" intersection, with very bad terrain just beyond the intersection. Indeed, the Saylor vehicle hit another vehicle in the intersection, then went airborne due to encountering the terrain, and finally was engulfed in fire once it stopped. It may have simply been a very bad choice to exit the freeway at that point and time, but we must concede that the driver was probably pretty busy and distracted at the moment. Also, this location is one of the rare instances where a freeway terminates with the straight-ahead lanes; to continue on the freeway here, you need to be in the two right (logically the exit) lanes. (The straight-ahead lanes are intended to continue the freeway North, at some undetermined future date.) Recent news is that a professor at Southern Illinois University has demonstrated uncontrolled acceleration by a single fault "short" condition of the redundant throttle position sensors. (Better details were not reported.) Toyota is backtracking from their initial pronouncement that the throttle system cannot have any electronic problems. My view at the present is that the possibility of a software problem is probably much higher than an electrical or electro-mechanical problem. We will have to wait for more facts, but the facts so far seem to be pushing Toyota's confidence back one step at a time. Ed Price [email protected] WB6WSN NARTE Certified EMC Engineer Electromagnetic Compatibility Lab Cubic Defense Applications San Diego, CA USA 858-505-2780 Military & Avionics EMC Is Our Specialty > -----Original Message----- > From: [email protected] [mailto:[email protected]] On Behalf Of Richard > Nute > Sent: Wednesday, February 24, 2010 12:29 PM > To: John Woodgate > Cc: [email protected] > Subject: Re: Toyota > > Hi John: > > > > There do seem to be some very odd features about this incident. Why > > wasn't the CHP officer making the 911 call, instead of the > hysterical > > person who did? > > The CHP off-duty officer was driving with his family > in the auto-dealer courtesy car. > > I guess he was pretty busy trying to control the car > (at 160 km/h), so his wife made the call. (I think > there's a web site where you can listen to the call.) > > > However, that is beside the point. Now that the focus has turned to > EMI > > being involved, and the practical impossibility of testing for all > > conceivable EMI threats, I think we are looking towards a > *mechanical* > > emergency throttle closer and/or fuel cut-off. > > > Have you ever had a computer lock up? Was it due to > EMI? Re-cycle power and everything runs normal. And > no trace to the cause of the lock-up. > > We owned a 2005 Toyota Avalon. We believe it incurred > an uncommanded acceleration which ended when we rear-ended > the car in front. This was moderate acceleration for a > long up-hill on-ramp to a freeway. Not fast, but it took > 2 feet on the brake and it slowed but not stopped until it > hit the car in front (which was stopped). At the time, we > blamed the brakes, but in light of the recent info, we now > believe it was an incident of uncommanded acceleration. > After front-end repair (including re-cycling the power), > the car worked normally for as long as we owned it. > > > Best regards, > Rich - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <[email protected]> All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc Graphics (in well-used formats), large files, etc. can be posted to that URL. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]>
