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Beth Stackpole
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Upside to the on-going debate
Beth Stackpole   7/25/2012 8:40:20 AM
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Hopefully rather than to point fingers or cast blame, this on-going debate will serve to spotlight the issue of tin whiskers and keep the potential problem on the front burner as engineers hit the drawing board on future designs. Obviously, it's a critical issue and potentially, a deadly problem if overlooked. So maybe the continued attention is a good thing.

Tim
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Re: Upside to the on-going debate
Tim   7/25/2012 8:53:03 AM
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Keeping the tin whisker problem on the forefront should help with future designs. Toyota is also very concerned with the floor mat issue. Our Toyota is a 2011, and the required 5000 mile preventive maintenance requires a floor mat inspection each time. They want to be sure this issue does not materialize again.

williamlweaver
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Re: Upside to the on-going debate
williamlweaver   7/25/2012 10:10:17 AM
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With two teenagers, my wife and I have 4 drivers in our household. We've owned 4 Toyota Corollas and are currently driving 3 of them which vary from 15k to 150k miles. We keep returning to Toyota because of the reliability and systematic build quality. I don't wish to bash the manufacturer, but we recently salvaged my wife's German car that was losing components faster than we could earn money to replace them. After we lost the transmission at 75K miles this summer, we traded it in for a two-year-old Corolla. Performing home repairs was near impossible and even a check of the transmission fluid level required a car lift and the removal of guards and plates under the car in order to reach the fill plug. The instructions for checking the level was to remove the plug and observe how much fluid escaped.
 
The Toyotas are extremely maintenance-friendly and our independent mechanic is delighted when we bring them in for routine service and inspection. Each component is designed with the other components in mind and the car as a whole is a tightly-integrated system even though (because) the individual components are not engineered to fine Swiss-craftsmen tolerances. I'm delighted to hear the Toyota engineers are being open with the debate.


ttemple
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Re: Upside to the on-going debate
ttemple   7/25/2012 10:26:58 AM
Since you wrote an advertisement for Toyota, why not go ahead and bash the other company by name?

 

williamlweaver
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Re: Upside to the on-going debate
williamlweaver   7/25/2012 10:47:39 AM
Hi ttemple... As a System Designer I praise good design whenever I see it. Electronics, hardware, software, education, administration - Like "fine art", I can recognize good design when I see it and like to praise it highly. 
 
It is a personal quirk of mine not to bash poor design. The trouble and expense we have had over the past five years of owning the "German" car were not individual lemon problems with bad components --- it was an overall failure of system design. The layout of the parts was a perfect example of "fallacy of  sub-optimization". It is wrong-headed to think that if all sub-components are optimized to near-zero tolerance the overall system will be improved. The truth is exactly the opposite.
 
System Design should concentrate on how out-of-tolerance behavior will be accommodated by the system as a whole, making it fault-tolerant and adaptive. The Toyota "J-Factor" is incorporated throughout the corporate culture (see here for example) and has been described recently:
 
"J-factor is known to be the DNA of Toyota design that synergizes various conflicting elements in harmony and give dimensions to new values. It is the element that defines the Japanese design structure, aesthetics and values that blend seamlessly with the global standards. One very good example of synergizing the contradictory element is the combination of engine power and electric motor to create hybrid vehicles. Likewise, many other elements of a car are well harmonized to give a completely new look and feel to every car. The j-factor is the trademark of Toyota's car design and it delivers an extremely striking and magnificent appeal." - link here 


Chuck_IAG
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Re: Upside to the on-going debate
Chuck_IAG   7/26/2012 10:29:03 AM
To Mr Weaver: with all due respect, it appears your comparison of the relative ease of servicing different brands of cars was comparing a standard transmission with an automatic.  Manual transmissions will always have a threaded (and inconvenient) plug to check the lubrication level, rather than a dipstick as do automatics; the fluids have different purposes and viscosities.  The same is true with Toyota stick shifts.  Having had a number of BMWs as well as a number of Toyotas (and 2 Lexuses), I know the engineering levels vary.  However, the downfall of the German engineering is their electronics, not their mechanics. My 1984 BMW 635CSi drive train was darn-near bulletproof and still cranked out well in excess of 130 MPH before I got too scared to push my luck, and traded it off last year (for, oddly, an older Toyota MR2).  I fear Toyota, "German cars," and any other manufacturer in the spotlight can be found "guilty" of cost/benefit tradeoffs.  My wife (the Lexus driver) calls it a witch hunt.

williamlweaver
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Platinum
Re: Upside to the on-going debate
williamlweaver   7/26/2012 1:06:48 PM
Hi Chuck-IAG... I'm actually a MOPAR fanboy and have owned a Dodge 400, Dodge Caravan, Dodge Stratus, Chrysler Sebring Convertible, Dodge Durango, and our current toy hauler is a 5.7L Jeep Grand Cherokee. I'm not a mechanic, but I have a code reader and a socket set and have switched out my share of thermostats, temperature sensors, oxygen sensors, and throttle-position sensors. We have put over 300K miles on the Corollas and the most I have had to switch out is light bulbs (thankfully).
 
The 2003 1.8L Turbo Automatic VW Convertible New Beetle was a different beast altogether. My wife fell in love with the styling and she is still heavily mourning its loss. My comments here were not to start a flame war, but on the topic of Design, the VW was in its own league.  I only learned that Volkswagen was the parent of Audi, Bentley, Bugatti, Lamborghini, Porsche, and Ducati  after we purchased the Bug from a reputable local dealer that sells only late-model used cars. What I didn't expect was that after the Bug started to lose sensors and electronic controllers that there are practically no user-serviceable parts and that we would need to take it to the dealer and pay Porsche repair prices for a VW. After a $9000 quote from the dealership to replace the trans at 75K we traded it in as salvage.
 
My overall point was that my experience with Toyota is not only have they been the most reliable cars we have owned, they are also the easiest to maintain -- designed with repair in mind. -- Rather than designed for exacting tolerances and then handed over to highly-skilled mechanics to fix when broken.
 
Perhaps some day when I have a Lamborghini repair budget on hand, I will consider VW again... 


Dave
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Gold
Re: Upside to the on-going debate
Dave   7/26/2012 2:47:58 PM
Chuck,

I agree with your wife. Toyota was unfairly "bashed" in many ways. The bottom line with the horrific crash of the ES350 in San Diego was a jammed carpet mat, a mat from an RX350 that had been installed inadvertently by a hired hand at the dealership. The crash had nothing to do with tin whiskers or any computer malfunction.

 I also would like to comment about German vehicles. Their overall reliability, according to Consumer Reports, is still well below that of many Japanese vehicles. Their performance and customer "pampering" lure in buyers who often overlook the inconvenience of having to take their vehicles in for not-very-infrequent repairs.

Rocketman
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Iron
Re: Upside to the on-going debate
Rocketman   7/26/2012 11:05:33 AM
I remember dealing with tin wiskers on wire wrap terrestrial sysems back in the 70's.  They were occuring between pins with 1/16 in spacing. Ok, so now I've been working with spacecraft and satellites for 25 years where there is one rule on this: don't use pure tin. I feel like saying "duh". 

naperlou
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Re: Upside to the on-going debate
naperlou   7/26/2012 9:57:18 AM
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Perhaps you should try some American brands. We have had one brand for many years now, covering several cars and many miles (over 150K). They are more stylish as well.

ttemple
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Re: Upside to the on-going debate
ttemple   7/26/2012 10:46:30 AM
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Amen to that naperlou.

I have a 2006 Malibu, over 100k miles on it, virtually no problems.  Easily gets mid 30's on the highway, mid 20's driving around town.  Got 80k miles on the original tires.

I drive a 1992 Cadillac Deville that has 202k miles on it.  Runs like a champ.  Springs a leak here and there every once in a while (my plumbing aint' what it used to be either!), but other than that it gets me around.  I get about 20 mpg, almost all around town driving.

I don't believe that the "J factor" cars are ultimately any better than "A factor" cars.  I have had both over the years, and I have had good experiences with both. I prefer current American built sedans to anything built.

John
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Re: Upside to the on-going debate
John   7/26/2012 12:09:47 PM
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I have yet to own an import and I am still holding on to my beloved '96 Caddy even though I recently bought a low mileage '03 F-150.  I have stayed away from imports because they didn't have enough torque to pull the hat off your head and you have to remove half a dozen components to get the alternator out of the engine compartment.  The torque ratings probably have improved since they do make a V8 now.  Don't know about the alternator thing though.  But with that said, I haven't been just thrilled with my F-150 either.  Don't get me wrong, its a fine truck, but there are things like lack of sound deadening and slow shifting transmission that I think could have been improved.  Maybe there is a "J" factor that isn't seen in America.  Heck, an F for an asian student is an -A.

Tim
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Re: Upside to the on-going debate
Tim   7/26/2012 12:29:41 PM
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I have an '02 Ford F150 with 125k, and outside of tires and brakes and tires, I have not had issue. I had a 94 F150 that at 50k miles needed a new universal assembly and a new clutch cylinder at 80k. Sometimes, I think that it is a crap shoot on vehicle quality.

Chet Brewer
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Iron
Re: Upside to the on-going debate
Chet Brewer   7/26/2012 9:47:53 AM
Tim, even more interesting was the experience of buying a new toyota recently, at delivery the sales person came out and gave me a canned pecture on the floor mats.

My experience after 2 months of driving it are that the pedals are not laid out particualry well for a tall person with big feet. On a couple of occasions I have hit the accelerater by accident and had trouble getting my foot off.

I do get depressed when senators decide to do design work however. They can't pass a budget but they can design electronic automobile controls

Charles Murray
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Re: Upside to the on-going debate
Charles Murray   8/8/2012 7:12:34 PM
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Good points on both counts, Chet Brewer. I agree that pedals in many vehicles are not well laid out for tall people with big feet. I would take it a step farther: Many tall people (6'-6" or taller) can't even fit into many of today's vehicles, let alone work the pedals. As for senators doing design work, I couldn't agree more.

Charles Murray
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More information
Charles Murray   7/25/2012 6:42:16 PM
After our story was turned in, NHTSA came back to us with a written statement about its position on this matter. There's not an iota of change in NHTSA's position, but I think it's worth posting anyway:

"As NHTSA and NASA indicated in our reports, the occurrence of "tin whiskers" is exceedingly rare and even when they are present, they do not appear to present any significant danger to drivers. We found that even if these tin whiskers created a small electrical short, they would not affect a driver's braking ability and would not cause the vehicle to accelerate out of control. As we identified and discussed in the reports, we have no reason to believe this could present a danger to drivers.

"In fact, NHTSA only knows of four occurrences of tin whiskers in a population of 1.7 million Camry vehicles. None of those occurrences involved any crashes or injuries and in each case, the vehicle entered a form of fail-safe operation that was so noticeable that the consumer quickly brought the vehicle in for repair."

tekochip
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Re: More information
tekochip   7/26/2012 7:47:55 AM
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Thanks Charles, the NHTSA is making a very solid determination.

Charles Murray
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Re: More information
Charles Murray   8/8/2012 7:08:12 PM
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 I agree, tekochip. Seems to me that NHTSA did its homework.

ab3a
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Re: More information
ab3a   7/26/2012 9:32:32 AM
I know several who would disagree. 

One of them is Bob Landman of HL Instruments. He and several others in NASA GSFC have been studying this problem for years.

This issue of tin whiskers is not new, and it is insidious. It was discovered during WW II and it is the reason we use lead based solder. Unless a solder is made with at least 3% lead alloy, it will start forming whiskers. The exact mechanism that causes this is not known, but the experimental evidence is incontrovertible.

All this nonsense got started because of the highly political and ignorant RoHS effort by the EU. Lead, as a material, has for all intents and purposes been declared "evil". I understand that we want to eliminate toxic waste from electronics, but if we make devices that become unreliable after just three years of service since manufacture (the average time it takes to grow a whisker to an adjacent contact), how environmentally sound is that?

Furthermore, with all the RoHS stuff in the supply chain, it is getting increasingly difficult to buy parts that aren't RoHS. Many will re-label parts as lead based, when they're not. This is very disconcerting to those who build high reliability devices or long lived devices such as spacecraft or safety systems.

Some progress has been made on a treatment that can be used to mitigate this problem, but it is still a long, intractable, and difficult issue.

Toyota is hardly the only company wrestling with this problem. This is an industry-wide problem that requires a political solution. The RoHS standards have run amok and need to be reigned in. 

Jake Brodsky

PS:  I wrote "3 years of service" when I should have written "3 years since manufacture."  Whiskers will grow whether the equipment is in service or sitting on the shelf. 

connectr
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Iron
Re: More information
connectr   7/26/2012 12:07:30 PM
Tin whiskers are not a new phenomena, but we used to have a bit of lead in our solder which prevented it. But with everyone going RoHS compliant, this is one of those results of the law of unintended consequences.

 

Keep in mind, when RoHS was first proposed and adopted, the primary usage of lead in electronics, was a pigment fixative in plastics. The darker the color, the more fixative was used. In the average consumer electronics equipment, something like >90% of the lead was in the plastic.

 

RoHS was never originally meant to touch our solders, because that was considered (at the time) too little a percentage to be worthwhile. If memory serves, the day that RoHS was adopted, Nokia dropped their 5 year warranty to 1 year because they were afraid of tin whiskers. Ahh, how times change!

 

 

Chris PE
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Gold
Re: More information
Chris PE   7/26/2012 12:37:47 PM
@ Connectr .Great point. Why do you think most of gadgets built in China,Korea, or any "inexpensive" countries die after a few month? Why all phone companies offer you a new phone every year , or two?

Answer is simple: whiskers! I found them on routers, modems,computers,tablets, card readers amplifiers ...too many to mention.One of our shuttles almost did not start , because on a last review they discovered whiskers on the mounting slides for PC boards. Lead was surely saving us from most of the problems.Military does not use ROHS anymore and some other industries are considering dropping it.All the lead hype came from plastics and paints more than solder. There is so much of disinformation out there. We need to believe scientists .

Whiskers grow on every metal and unless this is an alloy that contains whisker inhibitor (like lead in solder)they grow always, not  "on couple samples".Like I wrote in your previous post: tin, silver ,copper can grow in 24 hrs or less. Whiskers are not a coincidence - there are books on metalurgy that contain "whiskers" in many chapters , if not a whole book.

Thank you for support.

JimT@Future-Product-Innovations
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Re: More information
JimT@Future-Product-Innovations   7/26/2012 12:55:51 PM
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Jake- Thanks. Good, sound voice of logical and methodical reasoning.  Just the facts. Thank you - I rate you 5 stars. -JimT

mario.herrera
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Iron
Re: More information
mario.herrera   7/26/2012 3:40:10 PM
Unfortunately the RoHS regulations were only the beginning. Please read up on the EU's REACH laws. Conveniently located here: http://ec.europa.eu/environment/chemicals/reach/reach_intro.htm

My interpretation: If you can first prove that a substance in not harmful in any way to anything, you may be allowed to continue using it.

ttemple
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Platinum
Re: More information
ttemple   7/26/2012 10:36:43 AM

"In fact, NHTSA only knows of four occurrences of tin whiskers in a population of 1.7 million Camry vehicles. None of those occurrences involved any crashes or injuries and in each case, the vehicle entered a form of fail-safe operation that was so noticeable that the consumer quickly brought the vehicle in for repair."

 

What kind of rubbish is that?  It implies that they inspected 1.7 million vehicles.  How many did they actually look at? four? four thousand? forty thousand?  Certainly wasn't 1.7 million.

 

JimT@Future-Product-Innovations
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Re: More information
JimT@Future-Product-Innovations   7/26/2012 12:52:57 PM
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Charles, Thanks for reeling-in the conversation back to the details of the NTSB report; it was quickly degrading into an emotion debate over personal favorite car makers;  Off-Topic. How easily we all slip.

averagejoe72677
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Gold
Tin Whisker Headaches
averagejoe72677   7/26/2012 10:17:16 AM
Seems to me the EU in it's quest to eliminate lead as a pollution source has signed the death warrant of untold millions of electronic devices around the world. It isn't just automobile electronics that will suffer a premature death, it is just about all devices we buy and use everyday, washers, dryers, TV's cell phomes etc. There have been numerous post placed here over the last few years about tin whiskers causing electronic failures in all types of electronics. If indeed electronic throttle controls on cars are susceptable to this same fate as other electronic devices, then there should be a loud outcry worldwide to suspend ROHS compliance until a workable solution is found.

Stuart21
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Silver
Re: Tin Whisker Headaches
Stuart21   7/26/2012 11:25:12 AM
I am interested to know how the computer can distinguish between a throttle position giving a certain resistance and a tin whisker coincidentally producing the same resistance.

Would not encapsulation of soldered areas solve this problem?

tekochip
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Re: Tin Whisker Headaches
tekochip   7/26/2012 11:52:32 AM
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The typical method is to use a voltage divider so that a short to either rail or an open is an invalid reading.  monitoring for noise is also used to determine if the connection is intermittent, which is what will happen when the sensor starts to fail.  They usually open in the throttle position that is used the most, like at a highway cruise or idle.

averagejoe72677
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Gold
Re: Tin Whisker Headaches
averagejoe72677   7/26/2012 11:52:54 AM
I have thought of the encapsulation method myself, such as a spray on coating after assembly, but am not sure if this would prevent whisker growth. Perhaps someone with direct experience with the issue could chime in and answer the question. The real scary part of this is that any commercial aircraft built in the last 30 years are controlled by fly-by wire systems.  

ab3a
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Platinum
Re: Tin Whisker Headaches
ab3a   7/26/2012 12:43:37 PM
Encapsulation does almost nothing to stop whisker growth.  That approach has been tried by many without much success.  At best it delays the inevitable by a year or two, but the wiskers always win.

Chris PE
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Gold
Re: Tin Whisker Headaches
Chris PE   7/26/2012 2:03:46 PM
There are expensive methods to slow it down , but it includes special print on super-epoxy masks and increase of distance between PC board traces...and it is not inn today's world.Everything has to be tiny......and it breaks after 30 -90 days.Nothing , except metal inhibitors can stop whiskers' growth.You are absolutely right.

wbswenberg
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Re: Tin Whisker Headaches
wbswenberg   8/7/2012 3:09:21 PM
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In aerospace tin plate wire is a nono except for test equipment.  I believe the wiskers will grow right through the insulation.  So much for coating.

averagejoe72677
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Gold
Re: Tin Whisker Headaches
averagejoe72677   8/7/2012 3:58:47 PM
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Unless the electronics industry has a secret planned obsolence policy (would not surprise me), and ROHLS was not intended for the electronics industry (as others stated) why hang on to a lemon policy of continuing to use lead free solder? 

DVanditmars
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Silver
Re: Tin Whisker Headaches
DVanditmars   7/26/2012 3:10:32 PM
Most resisitive throttle position sensors will have two sensors, and for a given throttle position each sensor sends a different value.  With the different values for a given throttle position, the ECU can determine when there is a problem and go into the limp-home mode if required.

jmiller
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Re: Tin Whisker Headaches
jmiller   7/31/2012 8:46:08 PM
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Good question.  Also, why not have some duplicate feedback for some critical systems?

Chris PE
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Gold
Whiskers? Of course!
Chris PE   7/26/2012 12:02:06 PM
Charles, I hate to tell you "I told you so" , because I did comment on your previous blog where you definitevely rejected a possibility of whiskers "because NHTSA said so". Few cases in 1.7 million cars? Just a good cover-up.Most of customer have no idea what a dealer is doing to a car that was left for "car mat replacement".Anyhow , why would I take a word of NHTSA agains NASA? Only one of them consists of really credible scientists (no pun intended to the other one)It is a serious problem and it has to be addressed as such.A driver of a car does not quite know what to do in a panic situation.Sorry to say that but after seeing thousands "whisker cases" in many other devices I would dismiss car mats...

Regards,

Chris

Rob Spiegel
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Blogger
What component could cause acceleration?
Rob Spiegel   7/26/2012 1:37:19 PM
Nice article, Chuck. If tin whickers might be the failure that caused the unintended acceleration, that means a failed component could be the culprit. I would think the discovery is a matter of determining what component failure (if any) would result in unintended acceleration. 

MaxTom
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Iron
Tin Whiskers and Toyota
MaxTom   7/26/2012 1:59:05 PM
It's with interest and surprise to see the debate about the recent problem being addressed by Toyota. It was a surprise that it still being discussed. It,s also a surprise that the cause is still unknown or that a probable cause has not been articulated. Is it possible that tin whiskers caused the problem? The answer is yes but what is the probability that it is the cause. I would suggest that it's very low. Although we do not fully know what triggers the mechanism, there are a number of factors that have to be in place for it to occur such as humidity, material stress, humidity, etc. Also', we also know how to get rid of it So what is the big issue? If whiskers is the problem, why the debate?  

I would suggest that perhaps a different mechanism may be at work --- Fretting Corrosion. This mechanism is a result of low amplitudes of movement (as low as 0.001 to 0.003 of an inch) that can occur with all material systems including tin, nickel, copper and even gold (gold wears exposing under plate or other non-noble substrates). This mechanism does create momentary interruptions in electronic systems(we've been involved with this issue for since the 1970's). When a contact moves on a "bad" spot it will cause a fault. As motion continues the contact will move off the "bad" spot to a "good" spot and the fault will disappear.  These faults can be as fast as 2 nS. Unfortunately, fretting is not predictable.

 I will stop at this point. My frustration is that everyone is jumping on Toyota trying to fix the cause that is being described as tin whiskering. However, where is the conclusive data to show that it is. Fretting has a higher probability but there is no data to prove this either. Why can't Toyoata indicate what they have investigated with data to prove or disapprove the condition so we can move on to the next situation?

Chris PE
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Gold
Re: Tin Whiskers and Toyota
Chris PE   7/26/2012 2:13:52 PM
@Max-Tom,

Whiskers had been found and photographed by NASA scientists. There is no problem with the fact of whiskers.The problem is that we live in the world that covers the truth.They should just say:we found a problem.Bring the cars and we will correct it.Thing is that mat takes no time, changing design and construction of a module takes a lot of time.They are back on top and they will take care of their customers like they always did.They are probably using a supply of service parts now, which is a temporary fix, because they are defective like originals....unless problem is already fixed in those.

To other friends: We are talking about cars that were built after ROHS (no lead) rules.Toyota is not an exception.All electronics fails left and right and one year warranty disappeared from the market and is replaced with 90 years warranty.

A known fact is that most of electronics manufacturers give their products 4 years life span, which means that garbage can is a destination after 4 years.How about your parents, or grandparents 15 year old Zenith TV set.....well that's an ancient history.

studleylee
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Iron
Re: Tin Whiskers and Toyota
studleylee   7/26/2012 3:11:01 PM
There are actual images of whiskers on the control elements of the parts in question. That clears alot of the debut up I think.

http://www.eetimes.com/ContentEETimes/Images/Design/automotivedl/2012/ToyotaWhiskerClipLarge.jpg

http://www.eetimes.com/electronics-news/4234309/Toyota-accelerations-revisited-hanging-by-a--tin--whisker

studleylee
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Iron
Bring lead back to electronics.
studleylee   7/26/2012 3:06:16 PM
Bring lead back to electronics. Rohs is out of control on some critical elements that are needed for reliability and safety. Lead is exempt from censure in Avionics and should be also in automotive.

My personal belief is lead from improperly discarded batteries is the real issue. Not the trace amounts such as solder from PCBs. I think there are more naturally occuring toxic elements in soil.

Tom Drechsler
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Re: Bring lead back to electronics.
Tom Drechsler   7/26/2012 4:31:46 PM
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I think you will find that tin whiskers long preceeded the implementation of RoHS processes. That is a red herring.

studleylee
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Iron
Re: Bring lead back to electronics.
studleylee   7/26/2012 5:50:04 PM
That mostly occurred AFAIK in stannous tin plating of surfaces. The cure was to up the lead content. I may be wrong but thanks for adding. Related: I purchased an industrial PlasmaCutter a few years back and found it was DOA due to HyperTherm switching the assembly line over to rohs solder and components. The higher solder temps warped assemblies. They fixed it under warranty and it works fine. thx -Lee

BigEdRetired
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Re: Bring lead back to electronics.
BigEdRetired   7/26/2012 6:31:02 PM
"Tin Whiskers" were trouble makers before "Lead-Free".  Advoidance approaches are well known- cleanliness, use of conformal coatings, physical seperation of critical points, etc.  In addition, the method of using two sensors with different outputs on the petal and using logic in the receiving device gives additional assurance of being able to detect a failure and taking corrective action.

If all of the trouble advoidance procedures generally used with critical electronic controls are implemented, the failure is more probably a result of operator error or physical hardware failure.

Last but not least is the very high probability that the driver may have pressed the brake and the accelerator simultaneously.  Todays cars have the foot area so compact that drivers like myself (14EEE shoes) and women wearing heals cannot insure that they activate only the brake pedal. 

Note: Lead-Free electronics are generally banned from aircraft/spacecraft applications because of the supposedly possibility of tin whiskers.  LeadFree is not generally banned for other military applications and has been used for several years very sucessfully.

studleylee
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Iron
Re: Bring lead back to electronics.
studleylee   7/26/2012 6:46:09 PM
Agreed and good viewpoints to know. I don't really like the idea of not having a 'hard key' ignition. When I run my current rides to death, I will install a manual kill on whatever I get. I usually get 200K+ out of a car though, an EStop if you will :-)

robatnorcross
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Gold
Re: Bring lead back to electronics.
robatnorcross   7/26/2012 8:58:47 PM
"Several Years" doesn't quite cut it. Many military systems have to last for decades and have life or death consequences. Military systems must also endure really "bad" environments i.e. salt water, jungle humidity and heat among others.

I find it ironic that Grassley and his cohorts pretend to know about EVERYTHING. They allow Brussels (the EU) to dictate what the world does and then get all upset when things go to hell. They then start demanding explanations from people that they forced to comply to their previous bad decisions.

oldbikefixr
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Silver
Re: Bring lead back to electronics.
oldbikefixr   7/27/2012 5:37:59 PM
BigEd....lead was added to tin solder in the early 1900's to prevent the formation of tin whiskers.

Leaded solder connections do corrode when exposed to active elements, but that is not the same as tin whiskers. This corrosion can be reduced/prevented with the use of conformal coatings.

Tests with lead content vs whisker formation indicates that as little as 3% lead will prevent the formation of tin whiskers.

 

Chris PE
User Rank
Gold
Re: Bring lead back to electronics.
Chris PE   7/31/2012 4:05:49 PM
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Exactly!

Rob Spiegel
User Rank
Blogger
Re: Bring lead back to electronics.
Rob Spiegel   7/31/2012 7:26:30 PM
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Thyat's right, Oldbikefixr. And many argue that the 3 percent lead in the tin will not leach out into ground water at landfills. 

Chris PE
User Rank
Gold
We all make mistakes
Chris PE   7/27/2012 9:24:29 AM
We all make mistakes.ROHS was one of them. It cost billions of dollars in losses, equipment and defective products.As for military , I cannot give the name of a document, but in April this year all of military products have been taken off the ROHS requirement. There may be some electro - mechanical assemblies of high power  ,that still "linger" , but are on the way out.Car batteries are the highest concentration of lead in the environment, so stupid solder on PC board does not even matter.Needle in a stack! We all have to be realistic about this and Toyota cover-up was just a lie.

Tom Drechsler
User Rank
Silver
Re: We all make mistakes
Tom Drechsler   7/27/2012 11:29:32 AM
If the recylcing rate on consumer electronics approached that of car batteries, none of this would be necessary. All we have to do is implement a $15 core charge on every consumer electronics item, maybe $150 on every commercial electronics good. Instead, we ship it all to Nigeria ( or China or Vietnam) & let them extract the metals.

William K.
User Rank
Platinum
Tin Whisker Headaches
William K.   8/29/2012 10:13:20 PM
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I would say that any company dumb enough to use one single button for both the start and stop functions is certainly dumb enough to not recognize a failure when it happens, and not recognize a tin whisker faiure at all.

ON the other hand, why was our own federal automotive safety watchdog so blind as to allow the sales of a vehicle that had no failure proof means of shutting off the engine? A vehicle that did not even have a single purpose engine off switch? Who was paid off to let such an intrinsicly unsafe system be sold in this country?

The correct response would have simply been NO, with no compromise and no delays and no concern for profits that they would not make. They could have made it a 2 position run-stop switch and probably lives would have been saved. If the stop position had been a true stop switch and not just a computer input signal.

tekochip
User Rank
Platinum
Re: Tin Whisker Headaches
tekochip   9/2/2012 11:39:47 AM
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I agree, you need a real kill switch, not a switch that flags the processor, "pardon me, but when you have a spare microsecond could you please stop the car before I run into something."

William K.
User Rank
Platinum
Tin Whiskers and Stop Switches and Toy Otas
William K.   9/2/2012 5:27:59 PM
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In the auto plants in the USA, and also in many other plants in the USA, the big domed red button, the same shape as the start/stop button, is reserved for the emergency stop function. The only other function that can be assigned to a big red button is "normal stop", if it is the sameas "emergency stop". A machine using that button for any start type of function would not be allowed in the plant, for good reason.

The part that bothers me the most about that is that somebody in our country approved it. What was that dummy thinking?

chrisreed
User Rank
Bronze
Re: Tin Whiskers and Stop Switches and Toy Otas
chrisreed   12/20/2012 6:20:21 AM
NO RATINGS
The crisis trunk escape lever on some Lexus models is cheap plastic, claims Consumer Reports. This means that children, animals and possible feces pigeons stuck in Lexus trunks - should something of that nature ever occur - would have good trouble getting out via their own power. The right title car loans can help you out.



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