Toyota Throttle Electronics Easily Confused
in [Toyota Prius]
|
From: MLD on 27 Feb 2010 11:02 "jim beam" <me(a)privacy.net> wrote in message news:QKydnV3cOePUpRTWnZ2dnUVZ_t-dnZ2d(a)speakeasy.net... > On 02/27/2010 06:23 AM, MLD wrote: >> >> "jim beam" <me(a)privacy.net> wrote in message >> news:DM2dnWaVF4D_CBXWnZ2dnUVZ_tWdnZ2d(a)speakeasy.net... >>> On 02/25/2010 08:41 AM, MLD wrote: >>>> >>>>> <SNIP> >>>> <SNIP> >>>> >>>> My take on the sudden, uncontrolled acceleration is that it's root >>>> cause >>>> is tucked away somewhere in the electronics. Has anyone ever got >>>> involved in dealing with RFI (Radio Frequency Interference)? I've dealt >>>> with two interesting cases where RFI caused a significant problem in >>>> aircraft. One, complete loss of engine power. Cause was a radar signal >>>> that triggered the closing of a fuel Shut-Off Valve. Happened every >>>> time >>>> an aircraft (helicopter) flew past a particular radar station. >>> >>> this is a great post. the most important point is exactly this - "it >>> happens every time [state condition and result]". >>> >>> this is /not/ what is observed to be happening with toyota, otherwise >>> the results would be repeatable and investigatable. and occurring in >>> significantly greater numbers. >>> >>> >>> > The >>>> second, also a helicopter, two engines: Every time the pilot pushed the >>>> transmit button on his high frequency radio one engine rolled all the >>>> way back to its Idle setting--it recovered as soon as he released the >>>> button. The cause of both incidents was improper shielding of the >>>> aircraft wiring harnesses. The aircraft manufacturer was sloppy in his >>>> design--improved shielding fixed both problems. Cars now are more and >>>> more dependent on electronics and somehow can't shake the feeling that >>>> spurious signals are causing some of these unexplained incidents. >>> >>> good point, but if so, why are they not repeatable? people use cell >>> phones, cb radio, drive under power lines with gnarly harmonics all >>> the time - nothing. why would it suddenly happen to toyota just >>> because they stole gm's thunder in the cash-for-clunkers fiasco? >>> >>> >>>> As a >>>> side note; military electronics are subjected to rigid testing; >>>> bombarded with all kinds of RFI signals to determine if there is any >>>> undesirable behavior. I doubt if the automotive industry comes anywhere >>>> close to that kind of testing or evaluation. >>> >>> car electronics get all kinds of bombardment testing too - the "under >>> hood" environment is hugely hostile because of spark ignition >>> interference - the electronics have to not only survive, but survive >>> well.. >>> >>> >>>> MLD >>> >>> >> Your comments are valid. Having said that--the problem of being >> susceptible to any kind of electrical interference may not be a >> fundamental design issue but rather inadequate, sloppy, careless work >> procedures (you pick the word) during assembly/manufacture. That might >> account for why the total fleet has not affected and why only random >> individual cars end up with the problem. Purely speculation on my part. > > i'd buy that, but the probability fades to practically zero when you > factor in driver error as a cause. > > >> One thing that is required in Military/Commercial aircraft engine >> Control System design is a fault analysis that looks at each potential >> failure, which is then classified with respect to its severity and >> potential impact on the behavior of the engine/aircraft. Any failure >> that is classified as Class 1--severe loss of engine power, overspeed >> etc must be eliminated. Redesign is required to remove the Class 1 label. >> I would imagine that something along a similar vein is conducted in any >> system where safety and life is an issue--how rigorous and how much does >> cost play into the equation is open to question. >> MLD > > agreed. > > however, as a hardware example that tegger will confirm, the number of > verified honda engine computers failures is single digits. no amount of > talking can get around that hard evidence that honda are taking > reliability very seriously. i see no evidence that toyota are any > different. > > > -- > nomina rutrum rutrum Again no issue with your comments--but strange things happen and if you've been around long enough sooner or later you get to see some weird ones that come out of the blue completely unpredictable. Case-in-point---Two ECUs interconnected sending signals back and forth to each other. During operation they happened to be in different temperature environments. The flux residue on some solder joints actually created a millivolt signal as a result of the difference in their ambient temperatures. The mv signal was treated as a error signal that effected the behavior of the system. I think that we both agree that something is going on that can't be explained away by pointing to a stuck accelerator pedal and I don't think that it is a mechanical issue. MLD
From: jim beam on 27 Feb 2010 11:19 On 02/27/2010 08:02 AM, MLD wrote: > > "jim beam" <me(a)privacy.net> wrote in message > news:QKydnV3cOePUpRTWnZ2dnUVZ_t-dnZ2d(a)speakeasy.net... >> On 02/27/2010 06:23 AM, MLD wrote: >>> >>> "jim beam" <me(a)privacy.net> wrote in message >>> news:DM2dnWaVF4D_CBXWnZ2dnUVZ_tWdnZ2d(a)speakeasy.net... >>>> On 02/25/2010 08:41 AM, MLD wrote: >>>>> >>>>>> <SNIP> >>>>> <SNIP> >>>>> >>>>> My take on the sudden, uncontrolled acceleration is that it's root >>>>> cause >>>>> is tucked away somewhere in the electronics. Has anyone ever got >>>>> involved in dealing with RFI (Radio Frequency Interference)? I've >>>>> dealt >>>>> with two interesting cases where RFI caused a significant problem in >>>>> aircraft. One, complete loss of engine power. Cause was a radar signal >>>>> that triggered the closing of a fuel Shut-Off Valve. Happened every >>>>> time >>>>> an aircraft (helicopter) flew past a particular radar station. >>>> >>>> this is a great post. the most important point is exactly this - "it >>>> happens every time [state condition and result]". >>>> >>>> this is /not/ what is observed to be happening with toyota, otherwise >>>> the results would be repeatable and investigatable. and occurring in >>>> significantly greater numbers. >>>> >>>> >>>> > The >>>>> second, also a helicopter, two engines: Every time the pilot pushed >>>>> the >>>>> transmit button on his high frequency radio one engine rolled all the >>>>> way back to its Idle setting--it recovered as soon as he released the >>>>> button. The cause of both incidents was improper shielding of the >>>>> aircraft wiring harnesses. The aircraft manufacturer was sloppy in his >>>>> design--improved shielding fixed both problems. Cars now are more and >>>>> more dependent on electronics and somehow can't shake the feeling that >>>>> spurious signals are causing some of these unexplained incidents. >>>> >>>> good point, but if so, why are they not repeatable? people use cell >>>> phones, cb radio, drive under power lines with gnarly harmonics all >>>> the time - nothing. why would it suddenly happen to toyota just >>>> because they stole gm's thunder in the cash-for-clunkers fiasco? >>>> >>>> >>>>> As a >>>>> side note; military electronics are subjected to rigid testing; >>>>> bombarded with all kinds of RFI signals to determine if there is any >>>>> undesirable behavior. I doubt if the automotive industry comes >>>>> anywhere >>>>> close to that kind of testing or evaluation. >>>> >>>> car electronics get all kinds of bombardment testing too - the "under >>>> hood" environment is hugely hostile because of spark ignition >>>> interference - the electronics have to not only survive, but survive >>>> well.. >>>> >>>> >>>>> MLD >>>> >>>> >>> Your comments are valid. Having said that--the problem of being >>> susceptible to any kind of electrical interference may not be a >>> fundamental design issue but rather inadequate, sloppy, careless work >>> procedures (you pick the word) during assembly/manufacture. That might >>> account for why the total fleet has not affected and why only random >>> individual cars end up with the problem. Purely speculation on my part. >> >> i'd buy that, but the probability fades to practically zero when you >> factor in driver error as a cause. >> >> >>> One thing that is required in Military/Commercial aircraft engine >>> Control System design is a fault analysis that looks at each potential >>> failure, which is then classified with respect to its severity and >>> potential impact on the behavior of the engine/aircraft. Any failure >>> that is classified as Class 1--severe loss of engine power, overspeed >>> etc must be eliminated. Redesign is required to remove the Class 1 >>> label. >>> I would imagine that something along a similar vein is conducted in any >>> system where safety and life is an issue--how rigorous and how much does >>> cost play into the equation is open to question. >>> MLD >> >> agreed. >> >> however, as a hardware example that tegger will confirm, the number of >> verified honda engine computers failures is single digits. no amount >> of talking can get around that hard evidence that honda are taking >> reliability very seriously. i see no evidence that toyota are any >> different. >> >> >> -- >> nomina rutrum rutrum > > Again no issue with your comments--but strange things happen and if > you've been around long enough sooner or later you get to see some weird > ones that come out of the blue completely unpredictable. > Case-in-point---Two ECUs interconnected sending signals back and forth > to each other. During operation they happened to be in different > temperature environments. The flux residue on some solder joints > actually created a millivolt signal as a result of the difference in > their ambient temperatures. The mv signal was treated as a error signal > that effected the behavior of the system. then they should have been signaling digitally, not using analog. millivolt differences are not digital signal thresholds. > I think that we both agree that something is going on that can't be > explained away by pointing to a stuck accelerator pedal and I don't > think that it is a mechanical issue. > MLD no, we don't agree on that because i don't accept the presumption that "something is going on". the facts we have are very clear, despite all the hyteria, bullshit and astroturf: 1. there have been only two cars involved in fatalities. and in both cases, there is nothing to suggest there was a simultaneous failure of the vehicle's brakes, ignition switch or transmission selector that would have allowed the drivers to safely bring these vehicles to a halt. 2. we have a whitehouse getting directly involved in what should be an agency's job after the debacle called "cash for clunkers" backfired. this is a political systems failure dude, not electronics systems. -- nomina rutrum rutrum
From: Bob Cooper on 27 Feb 2010 13:33 In article <dbadnQQMhN-Y2xTWnZ2dnUVZ_i2dnZ2d(a)speakeasy.net>, me(a)privacy.net says... > > On 02/27/2010 08:02 AM, MLD wrote: > > > > Case-in-point---Two ECUs interconnected sending signals back and >>> forth > > to each other. During operation they happened to be in different > > temperature environments. The flux residue on some solder joints > > actually created a millivolt signal as a result of the difference in > > their ambient temperatures. The mv signal was treated as a error signal > > that effected the behavior of the system. > > then they should have been signaling digitally, not using analog. > millivolt differences are not digital signal thresholds. > Total nonsense, said merely to say something. > > > I think that we both agree that something is going on that can't be > > explained away by pointing to a stuck accelerator pedal and I don't > > think that it is a mechanical issue. > > MLD > MLD, though you have made some valid technical points, your judgement is lacking in evaluating personalities. You're are talking to a madman, and he won't agree with you. > no, we don't agree on that because i don't accept the presumption that > "something is going on". the facts we have are very clear, despite all > the hyteria, bullshit and astroturf: > > 1. there have been only two cars involved in fatalities. and in both > cases, there is nothing to suggest there was a simultaneous failure of > the vehicle's brakes, ignition switch or transmission selector that > would have allowed the drivers to safely bring these vehicles to a halt. > There are many more than 2 Toyotas reported to have "unintentionally accelerated." > 2. we have a whitehouse getting directly involved in what should be an > agency's job after the debacle called "cash for clunkers" backfired. > This might help. Maintenance advice. http://www.ehow.com/how_2352403_clean-tin.html "Clean your tin hat with plain dish washing soap and a soft cloth. If your tin gets dirty you can clean it with a little dish soap and a soft cloth. Be sure to remove all of the soap and water with a dry cloth so your tin will not rust." > this is a political systems failure dude, not electronics systems. Dittohead.
From: jim beam on 27 Feb 2010 14:04 On 02/27/2010 10:33 AM, Bob Cooper wrote: > In article<dbadnQQMhN-Y2xTWnZ2dnUVZ_i2dnZ2d(a)speakeasy.net>, > me(a)privacy.net says... >> >> On 02/27/2010 08:02 AM, MLD wrote: >>> >>> Case-in-point---Two ECUs interconnected sending signals back and>>> > forth >>> to each other. During operation they happened to be in different >>> temperature environments. The flux residue on some solder joints >>> actually created a millivolt signal as a result of the difference in >>> their ambient temperatures. The mv signal was treated as a error signal >>> that effected the behavior of the system. >> >> then they should have been signaling digitally, not using analog. >> millivolt differences are not digital signal thresholds. >> > Total nonsense, said merely to say something. er, are you disputing the physical fundamentals, or are you just trying to prove that you don't understand what's being said? >> >>> I think that we both agree that something is going on that can't be >>> explained away by pointing to a stuck accelerator pedal and I don't >>> think that it is a mechanical issue. >>> MLD >> > MLD, though you have made some valid technical points, your judgement is > lacking in evaluating personalities. > You're are talking to a madman, and he won't agree with you. yeah, i'm completely insane - i just won't shut up when idiots keep being ignorant in public or can't pay attention to the facts. > >> no, we don't agree on that because i don't accept the presumption that >> "something is going on". the facts we have are very clear, despite all >> the hyteria, bullshit and astroturf: >> >> 1. there have been only two cars involved in fatalities. and in both >> cases, there is nothing to suggest there was a simultaneous failure of >> the vehicle's brakes, ignition switch or transmission selector that >> would have allowed the drivers to safely bring these vehicles to a halt. >> > There are many more than 2 Toyotas reported to have "unintentionally > accelerated." there are two involving fatalities. and zero distinguishable from driver error. > >> 2. we have a whitehouse getting directly involved in what should be an >> agency's job after the debacle called "cash for clunkers" backfired. >> > This might help. Maintenance advice. > http://www.ehow.com/how_2352403_clean-tin.html > "Clean your tin hat with plain dish washing soap and a soft cloth. If > your tin gets dirty you can clean it with a little dish soap and a soft > cloth. Be sure to remove all of the soap and water with a dry cloth so > your tin will not rust." why do you even have that bookmarked? is everyone that posts something you can't understand or simply don't like automatically a tinfoil head? > >> this is a political systems failure dude, not electronics systems. > > Dittohead. that more than one person can call a spade a spade makes them dittoheads? dude, you need a clue. -- nomina rutrum rutrum
From: Hachiroku ハチロク on 27 Feb 2010 14:39
On Sat, 27 Feb 2010 12:33:59 -0600, Bob Cooper wrote: > >> this is a political systems failure dude, not electronics systems. > > Dittohead. Boob. There. I corrected your name for you. |