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Discussion Starter #1
It is a scary thought if this is anything to do with the reason for sudden acceleration.



Electromagnetic inference (EMI) as a cause of Toyota's unintended acceleration woes: That's the latest allegation. And one that Toyota quickly rebutted, which is not the same as saying successfully refuted. EMI is scary in theory: The electronic devices we carry with us such as cellphones, laptops, and iPods emit radio waves that might interfere with cars, pacemakers, or the airplanes we fly in. This potential cause was highlighted today in a press conference by Tom Murray, an Ohio lawyer who's filed dozens of unintended-acceleration lawsuits the last two decades.

EMI problems, if they exist, are hard to prove or disprove. An unintended-acceleration glitch that happens every 100 million miles of driving could be dangerous on the whole to a handful of motorists, but the odds are dramatically against it affecting any one car. For most of the 20th century, the functions of a car were purely mechanical: With a little training, you could look at a carburetor, throttle cable, or hydraulic brake and figure how it worked. It's different where a bunch of wires go into one end of black box and the other end connects to an actuator or still more wires. Statistically, x-by-wire systems (drive-by-wire, brake-by-wire, throttle-by-wire, eventually-steer-by-wire) are far safer than mechanical systems. That's why planes are now fly-by-wire, and you don't see them falling out of the skies. But it's also hard to prove safety of electronic systems to critics or the public, especially when your credibility is suffering.
Toyota's Worst Nightmare: EMI-Linked Unintended Acceleration - Gearlog
 

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There was a story on the local news the other night, of a woman who was killed in November. her Rav4 crossed the center line on a highway and head on into a transport truck. There was no known cause for the accident (at the time). this was shortly before the massive Toyota recall, Rav4's were on that recall list.
Her husband was on the news because he tried to take his Highlander back, because he han't help wonder if that is what killed his wife. Toyota said absolutely not, as it would "set a precident". Imagine, living with your spouse's death, never knowing if it was caused by a defective part on their vehicle. =(
 

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The older VW Type 3's made from 1968-1974 (Station wagons and fast backs) used the older K-Jetronic and J-Jetronic Bosh Fuel Injection system. They had strange blips with the engine cutting out once in a while. It was traced to CB radios that had been tinkered with for more power. So EMI can cause problems. We build homemade shields that were grounded to the frame to stop it. The electronics on airplanes all have some sort of shelding to prevent this or so I'm told.
 

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Discussion Starter #4
There was a story on the local news the other night, of a woman who was killed in November. her Rav4 crossed the center line on a highway and head on into a transport truck. There was no known cause for the accident (at the time). this was shortly before the massive Toyota recall, Rav4's were on that recall list.
Her husband was on the news because he tried to take his Highlander back, because he han't help wonder if that is what killed his wife. Toyota said absolutely not, as it would "set a precident". Imagine, living with your spouse's death, never knowing if it was caused by a defective part on their vehicle. =(
That is SO sad. I cannot begin to imagine losing a partner this way. Just tragic.

I was reading today that a Lexus that recently crashed with the accelerator fault was the same vehicle that a couple of weeks earlier had run away with another person in exactly the same area of the freeway. That area has big power lines which they think could be the cause.
 

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EMI and RFI are a battle for designers in the auto world. It is only going to get worse. I doubt this interference will be root cause for the acceleration. I think Toyota (almost all auto mfgs) have a good handle on this or they would have had a host other car system problems well before this accelerator problem. I think some cheap ass vendor screwed up on the speed control sensor.
 

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That is SO sad. I cannot begin to imagine losing a partner this way. Just tragic.

I was reading today that a Lexus that recently crashed with the accelerator fault was the same vehicle that a couple of weeks earlier had run away with another person in exactly the same area of the freeway. That area has big power lines which they think could be the cause.
A lot of people don't realize that Lexus is made by Toyota. I wonder if they'll end up recalling these too.
 

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A lot of people don't realize that Lexus is made by Toyota. I wonder if they'll end up recalling these too.
That is why I think this is a vendor quality issue. Typically higher end cars have better subcomponents. The lexus portion prides themselves on quality along with luxury. In order to keep loyalty in the Lexus brand with the customers, the car has to have the least amount of problems.

Some of you might remember when Jaguar introduced the S type. It was nothing more than a dressed up Ford Taurus. Jaguars failure to convince the luxury car buying public that they were getting a true luxury car was that too many of the powertrain components were straight from the Taurus parts inventory. The Jag S type had the same problems that the Taurus had for a whole lot less money.
 

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EMI/RFI can create significant issues in electronic devices. This is very true. However, testing devices for emissions and/or susceptability has been around for a long time. Anything that goes into an aircraft is tested for susceptability and emissions. Anything used in the defense business also. Anything used in the home, is tested for emission, i.e. won't mess up your TV. Your microwave is tested, won't cook you while you stand waiting for your coffee. I do not know if auto parts are tested or not. I have a hard time accepting that they aren't, but do not know. Of course, who tests these things? The manufacturer does the tested, generates a report, and sends it to the government for a rubber stamp.
 

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Discussion Starter #9 (Edited)
That is why I think this is a vendor quality issue. Typically higher end cars have better subcomponents. The lexus portion prides themselves on quality along with luxury. In order to keep loyalty in the Lexus brand with the customers, the car has to have the least amount of problems.
I think you have a good point. Lexus are built in smaller numbers compared with Toyotas mainstream cars. They have had new models in the past which have had wait lists. Take the RX400h for example. People were waiting for 2-3 months to get one when that first came out. This also keeps the price high as well.

In 2007 Lexus was having the problem with the gas pedal sticking although at the time they said it was the floor mat. I tried to replicate the problem in a Lexus and found I could. When I put one of their rubber mats on top of the carpet mat I could get the gas pedal to stick underneath. People at the time were warned about this and told to remove the carpet mats before installing rubber ones.
 

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EMI/RFI can create significant issues in electronic devices. This is very true. However, testing devices for emissions and/or susceptability has been around for a long time. Anything that goes into an aircraft is tested for susceptability and emissions. Anything used in the defense business also. Anything used in the home, is tested for emission, i.e. won't mess up your TV. Your microwave is tested, won't cook you while you stand waiting for your coffee. I do not know if auto parts are tested or not. I have a hard time accepting that they aren't, but do not know. Of course, who tests these things? The manufacturer does the tested, generates a report, and sends it to the government for a rubber stamp.
We use independent labs to verify or refute vendor component testing. My work partner does several quality audits a month at various vendors. The problem lies in each component going to the assembly floor is not fully tested. Depending on the part we might do quality checks at delivery (incoming inspection) and that might be a predetermined sample set. We also do First article inspections on newly designed parts. This is a rigorous inspection. One thing that happens is that a sub-component vendor might ask for a deviation on occasion where they want to change a process. This is not uncommon and often after engineering review the deviation is granted. Any where along the inspection path something could be missed. In the case of the Toyota accelerator a missing shield or a gapped shield in the harness can be the door way for the EMI/RFI noise. It will be interesting to see the root cause and I will bet it was a deviation form the original design.
 
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