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E90/E91/E92/E93 (2006 - 2013)
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  #26  
Old 11-07-2009, 08:27 AM
wit3356 wit3356 is offline
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Originally Posted by Emission View Post
Agreed. Most should not try this.

However, I do this sort of thing for a living. I'm an automotive journalist and I test (um... flog) cars for a paycheck. (I also race Porsches for fun.)

I've done dozens of "launch control" starts in the Porsche 911 Turbo PDK, Porsche 911 C4S PDK, Porsche Boxster S PDK, and Porsche Panamera Turbo PDK... and in many other cars. As a result, I am well aware of how vehicles will handle. In fact, the more I test... the more experienced I become.

In all honesty, I suggest you try your PDK "launch control" on an empty road soon. You will understand your car's capabilities, plus you will learn how to react under heavy acceleration. Testing is a good thing, and it prepares you for an emergency.

The Highway Patrol officer died because he did not completely understand the vehicle he was driving. He was unfamiliar with the controls and operation of the Lexus loaner.

Did we ever welcome you to Bimmerfest?

- Mike
Wow. It must be a fun job. Thanks much. Great to hear the comments and a welcome from a professional driver. I like driving fast cars, but I haven't tried such heavy acceleration on the road. Crowed Southern CA road is no good to try that. It might be a fun to try on an open load unless I get stopped for speeding.

Even though it is a loaner car, I believe most stop and go functions are the same, right? I drive rental cars frequently, and usually pick up different cars to try although they are not good cars. I drive off after checking only the engine turn on-off. I don't check any electronics settings and the gas and brake location. Alhough the police officer was not familiar wiith the loaner, it is unlikely for him to speed the car to 120MPH by mistakes. If the cruise control was wrongly set, it should have been braked quickly. His brother even had a time to call CHP before the crash, and I cannot imagine what happened for that long time.

I heard last night from one of my friends about his experience of the runaway car. He lives in Florida, and once drove an American car. On highway, the engine ran up to over 4000RPM, and he barely stopped it with the Neutral gear. After several weeks, he had another run like that. This time he couldn't stop, and he turned the engine off after getting into the shoulder. Even after that stop, the car started ok like nothing happened. He traded the car in for another car, and suggested the same to me.

As I mentioned in my last reply, I had the Check Engine Light on a couple times when starting. I think it is an obvious faulty state, but the dealer told me there are no defects in the car since there is no error message left in the computer. I couldn't replicate the same condition. We consider such fails normal assuming that cars can break down.
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  #27  
Old 11-07-2009, 08:42 AM
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Just an FYI, consumer reports did a test in the same exact car showing what should have been done. They took the car up to 80mph put a foot on the brake and then put the car into neutral. Our local news showed the video a couple days after the accident.

In general, I believe everyone should go to defensive driving school at some point because the BS driving tests they administer in the USA are just plain bogus.
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  #28  
Old 11-07-2009, 10:19 AM
wit3356 wit3356 is offline
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Originally Posted by Pedal2Floor View Post
Just an FYI, consumer reports did a test in the same exact car showing what should have been done. They took the car up to 80mph put a foot on the brake and then put the car into neutral. Our local news showed the video a couple days after the accident.

In general, I believe everyone should go to defensive driving school at some point because the BS driving tests they administer in the USA are just plain bogus.
Right. Everyone should be prepared for safe driving. Otherwise, it is very likely to lose our composure when we need it most. Things can get worse and out of control if not prepared. Happy driving.
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  #29  
Old 11-07-2009, 11:58 AM
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Originally Posted by wit3356 View Post
Please don't try such dangerous stunt with the floored gas and brake. You know my Porsche has the Sport II option with a launch control. It is exactly what you tried. They can cut 0 to 60 time by 0.2sec. The launch control works like this. At the stop, you press the gas and brake together to rev the engine at the full throttle. When the green light is on, you just release the brake to launch the rocket. It is a dangerous option I haven't even tried.
What's so 'dangerous' about launch control?
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  #30  
Old 11-07-2009, 02:34 PM
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Originally Posted by wit3356 View Post
Wow. It must be a fun job. Thanks much. Great to hear the comments and a welcome from a professional driver. I like driving fast cars, but I haven't tried such heavy acceleration on the road. Crowed Southern CA road is no good to try that. It might be a fun to try on an open load unless I get stopped for speeding.

Even though it is a loaner car, I believe most stop and go functions are the same, right? I drive rental cars frequently, and usually pick up different cars to try although they are not good cars. I drive off after checking only the engine turn on-off. I don't check any electronics settings and the gas and brake location. Alhough the police officer was not familiar wiith the loaner, it is unlikely for him to speed the car to 120MPH by mistakes. If the cruise control was wrongly set, it should have been braked quickly. His brother even had a time to call CHP before the crash, and I cannot imagine what happened for that long time.
It is an absolute blast.

While most stop/go functions are standardized on cars (gas pedal on right, brake pedal on left, turn signal on left stalk, etc...) the START/STOP button is still relatively new and there still isn't a standardized industry-wide way of making it work. However, in general, holding it for three seconds will shut off the vehicle. In a BMW, you can also stab it quickly three times and it will kill the engine. Of course, there is always neutral...

- Mike
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  #31  
Old 11-07-2009, 02:38 PM
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Originally Posted by Pedal2Floor View Post
Just an FYI, consumer reports did a test in the same exact car showing what should have been done. They took the car up to 80mph put a foot on the brake and then put the car into neutral. Our local news showed the video a couple days after the accident.

In general, I believe everyone should go to defensive driving school at some point because the BS driving tests they administer in the USA are just plain bogus.
I spoke on the phone to the engineers at Consumer Reports. They ran the test several times, and each time shifting the vehicle into NEUTRAL stopped it quickly and safely. I also spoke in the phone to the engineers at BMW about the same thing. They reminded me that no late-model BMW with a START/STOP button has a steering wheel lock... you can ALWAYS steer a BMW (even if the keys are not in the vehicle!).

+1 on the Defensive Driving School.

- Mike
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  #32  
Old 11-07-2009, 02:41 PM
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Originally Posted by Emission View Post
I spoke on the phone to the engineers at Consumer Reports. They ran the test several times, and each time shifting the vehicle into NEUTRAL stopped it quickly and safely. I also spoke in the phone to the engineers at BMW about the same thing. They reminded me that no late-model BMW with a START/STOP button has a steering wheel lock... you can ALWAYS steer a BMW (even if the keys are not in the vehicle!).

+1 on the Defensive Driving School.

- Mike
Funny, I unofficially found the same thing, but thought it was because I have a manual or because the comfort access keyfob was in my pocket. Under NO conditions could I get the steering wheel to lock. You could always steer, car on or off, key in or out. Interesting...
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  #33  
Old 11-07-2009, 02:43 PM
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Funny, I unofficially found the same thing, but thought it was because I have a manual or because the comfort access keyfob was in my pocket. Under NO conditions could I get the steering wheel to lock. You could always steer, car on or off, key in or out. Interesting...
On second thought, doesn't this make the cars very easy to steal? Just hook up the tow cable, break a window, hop in, put it in neutral, and tow it away? I suppose nothing guards against a flatbad anyway...
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  #34  
Old 11-07-2009, 02:44 PM
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Originally Posted by neapolitan View Post
Funny, I unofficially found the same thing, but thought it was because I have a manual or because the comfort access keyfob was in my pocket. Under NO conditions could I get the steering wheel to lock. You could always steer, car on or off, key in or out. Interesting...
I never knew it until the day the engineer from BMW called me last month. I walked out the X5 in our garage, opened the passenger door... leaned over and turned the steering wheel! Who knew?

- Mike
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Gone, but never forgotten... my E70 X5 35d, E90 335i, E46 330i, E36 328i, E70 X5 3.0si, E53 X5 3.0i.
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  #35  
Old 11-07-2009, 02:49 PM
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Originally Posted by Beenthere View Post
There is nothing particularly dangerous about launch control. [/B]
It is actually BETTER on the car than doing it with your own feet (side-stepping the clutch).

Launch Control software coordinates the clutch release and throttle PERFECTLY to limit slippage and wear. In addition, the software has been programmed (in a Porsche, at least) to retard throttle for the millisecond after the engagement to reduce driveline shock. It is imperceptible to the driver.

Porsche says you can do launch control all day long, from each start. Your neck would hurt, but your warranty is unaffected.

- Mike
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'15 Volkswagen Golf TDI 6MT
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Gone, but never forgotten... my E70 X5 35d, E90 335i, E46 330i, E36 328i, E70 X5 3.0si, E53 X5 3.0i.
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  #36  
Old 11-07-2009, 05:50 PM
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If you go to the "other" thread on the Lexus crash you'll see this has been discussed to death from every possible angle including pure fantasy.

http://www.bimmerfest.com/forums/sho...ht=lexus+crash

The sad reality is this incident and the fatalities were completely preventable had the driver made any of the proper choices below:

1. Applied the brakes properly and stopped the vehicle instead of riding the brakes until they burned out

2. Shifting the trans into neutral

3. Shutting the ignition off

While some folks don't fully agree with the above facts, they are true none the less.

Hopefully other folks will learn from this tragedy what your car is capable of and what the proper choices are in an emergency so that you don't become a statistic. An educated driver often makes better decisions in an emergency than a driver with minimal skills and knowledge.

I highly recommend the thirty second brake test be performed in a safe environment so that you see what your brakes can do and what to expect in the very unlikely situation of a stuck throttle in your vehicle. If you can't conduct this test safely you really do not have the proper skills to be driving and should not be allowed on the roadways until you do have proper skills.

Please note:

While this brake test should be a requirement of any driving course or licensing process, you conduct this at your own risk. I in no way accept any responsibility for other peoples actions to determine the braking capabilities of their vehicle in a safe and proper manner.

Thanks for the information. There have been so many discussions already there, and most comments were useful. I learned a lot, and also mentally prepared myself for such situation.

By the way, the majority of the comments were blaming the victim for not being able to free them by taking a few basic steps. I think we need to learn something from this case. There were no discussions on the risk we take driving modern cars controlled by the ECM in the drive-by-wire system. In my expereince, my car jumped almost 13 feet instantly before I realized that the crash onto the guard rail was unavoidable.
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  #37  
Old 11-07-2009, 05:54 PM
wit3356 wit3356 is offline
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What's so 'dangerous' about launch control?
You already saw so many replies on this. It was my personal opinion.
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  #38  
Old 11-07-2009, 07:03 PM
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Emission Emission is offline
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There were no discussions on the risk we take driving modern cars controlled by the ECM in the drive-by-wire system.
Modern cars with drive-by-wire (DBW) are light-years safer than those early cars without the system. In fact DBW is just one of the components of electronic stability control... another lifesaver.

- Mike
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'15 Volkswagen Golf TDI 6MT
'86 Porsche 911 Turbo 4MT


Gone, but never forgotten... my E70 X5 35d, E90 335i, E46 330i, E36 328i, E70 X5 3.0si, E53 X5 3.0i.
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  #39  
Old 11-07-2009, 08:27 PM
wit3356 wit3356 is offline
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Originally Posted by Beenthere View Post
The DBW really had no influence on the situation. If it had been a mechanical throttle cable instead of DBW the car still would have traveled the same distance if you pressed on the accelerator pedal instead of the brake pedal. The ECM and DBW are not the problem. Unfortunately it's driver error that leads to these avoidable incidents. Glad no one was injured.

Driver error!! Well I hope so. Otherwise, I would not feel like driving further. We may want to believe cars are more reliable than they are though. Happy driving.
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  #40  
Old 11-07-2009, 09:52 PM
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Driver error!! Well I hope so. Otherwise, I would not feel like driving further. We may want to believe cars are more reliable than they are though. Happy driving.
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  #41  
Old 11-07-2009, 10:14 PM
wit3356 wit3356 is offline
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Well, the class-action suit was finally filed today in LA against Toyota for their unintended acceleration. I am not sure, but aren't Lexus and BMW buying the same ETC or ECM from the same OEM vendor?
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  #42  
Old 11-07-2009, 10:41 PM
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Not likely but not relevant either as the programming is what counts, not who supplies the box. The box wasn't the problem, the floor mat was the issue that led to the stuck throttle.
Toyata already recalled the floor mat. The class action is not on the floor mat but on the ETC. The suit demands the ETC recall. The software is correct only when the computer is operating normally. The situation occurs when the computer decides what the driver is doing - not the driver. It appears that the Toyota case may end up with their admitting the possiblity of ETC system faults, which all car manufacturers would like to emphatically deny.
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  #43  
Old 11-08-2009, 10:04 AM
wit3356 wit3356 is offline
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In America the judicial system makes lawyers rich and justice rare.
I agree with you. It is a joke, but half of the world lawyers are in the US, and its half are in California. It is easy to bash lawyers, but there should be something more to this class action. I donít think it is the Toyotaís isolated problem. No car is safe, and BMW is no exception. Simply, there are more Toyotas on the street. That is why. I also agree that most complaints would be driver errors.

Let me elaborate my point a little with this long my 2-cent ENG101. I have a Ph.D in electrical engineering, and have taught, researched, and practiced semiconductor chip designs for computers and communications. You may be carrying electronic gadgets with some of my designs in them. I know that someone will say that the Ph.D doesnít necessarily make a good engineer in the same argument the CHP officer died in the Lexus crash was not necessarily a good driver. Ok, frankly, I am embarrassed to see most Bimmers on this site are sure that cars donít fail but drivers do, and also that Toyota fails but BMW donít. This case, cars are recent more electronically-controlled ones. See how many the HPFP problems in 335i are reported. You may say yes, but it is a different case. All mechanical and electronic parts and even computers fail, so do any systems made out of them. Letís assume the car brake broke down. There are three cases. The on-board computers either show the brake fail, or no fail. The former is the common case we consider. The latter case is when the stupid system is not even working. If things happen consistently, we can say that the systems or computers still work. The risky fault or fail state is neither of these cases when computers show the brake fail most of the time, and every once in a while they donít show.

I once explained my experience with the start-up problem showing the Check Engine Light. That is this third case. To computers, it is the same faulty state as the sudden acceleration if you allow me to use this fault term. I considered it seriously, and brought my car to the dealerís attention only to be told that there were no problems in my cars as the on-board computer doesnít show any trace of the faults. Computers have no intelligence like us. Most of us will say the brake failure consistently unless we want to lie once we confirmed it. In the Computer Science field, they have tried to make computers imitating human intelligence. The field is called artificial intelligence. But usually such systems with human intelligence do not exist, and if they work in some limited situations, they are called expert systems. Computers donít know what they are doing. Garbage in garbage out.

I suspect the car's fault, probably the engine CPU or its software. Again such faulty states occur rarely, but they can. These days most high end cars have an electronic accelerator with no pedal connected to the throttle mechanically. The engine CPU controls the throttle as well as the fuel injection. Even if it's not faulty software, it could be a hardware glitch, either in the CPU memory or the pedal position sensors. If you estimate the soft memory or instruction error probability inside the CPU and multiply that by the number of cycles it is written or read per second, and factor in the number of hours the car is driven, you can see how often a wrong value could be sent to the throttle position servo. I bet most manufacturers don't have redundant or fault-tolerant software to catch this. Fault-tolerant computing starts from identifying faults to correct them. In my Check Engine Light at Start proves that such faults were not identified in my BMW. Some of you may still say that computers cannot be wrong. Yes, they are. Can you believe in some locations in the US, computers can break down more frequently? It is not the myth. Even radiation can change computer data. So NASA or military want their electronics radiation-hardened. There are more intense cosmic rays in space. Fault-tolerant systems result both from robust hardware and software designs.

I believe the black box should now be mandatory for cars so that faulty events can be recorded to clear up whose faults they are Ė car or driver. It will help with insurance, warranty, law suit, etc. And manufacturers can fix the bugs early before bad accidents happen. But they still should video-tape the motion of the driversí foot together with other electronic info. Until then, this controversy will continue.

Thanks if you finished reading. Again happy driving.
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  #44  
Old 11-08-2009, 11:54 AM
NickHW NickHW is offline
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I bet most manufacturers don't have redundant or fault-tolerant software to catch this. Fault-tolerant computing starts from identifying faults to correct them.
Take it from me that you are teaching granny to suck eggs. Like you said, it's ENG101.

There're whole industries based around safety case production, FMECA, software safety and so on. Mostly from the aerospace industry initially, but the same consultancies now work with the automotive industry. I used to work with a consultancy that did the TbW software verification for a major US manufacturer; it looked a whole lot like the V&V projects we'd done for things like weapons computers for fighter planes.
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  #45  
Old 11-08-2009, 11:55 AM
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Originally Posted by wit3356 View Post
I agree with you. It is a joke, but half of the world lawyers are in the US, and its half are in California. It is easy to bash lawyers, but there should be something more to this class action. I don't think it is the Toyota's isolated problem. No car is safe, and BMW is no exception. Simply, there are more Toyotas on the street. That is why. I also agree that most complaints would be driver errors.

Let me elaborate my point a little with this long my 2-cent ENG101. I have a Ph.D in electrical engineering, and have taught, researched, and practiced semiconductor chip designs for computers and communications. You may be carrying electronic gadgets with some of my designs in them. I know that someone will say that the Ph.D doesn't necessarily make a good engineer in the same argument the CHP officer died in the Lexus crash was not necessarily a good driver. Ok, frankly, I am embarrassed to see most Bimmers on this site are sure that cars don't fail but drivers do, and also that Toyota fails but BMW don't. This case, cars are recent more electronically-controlled ones. See how many the HPFP problems in 335i are reported. You may say yes, but it is a different case. All mechanical and electronic parts and even computers fail, so do any systems made out of them. Let's assume the car brake broke down. There are three cases. The on-board computers either show the brake fail, or no fail. The former is the common case we consider. The latter case is when the stupid system is not even working. If things happen consistently, we can say that the systems or computers still work. The risky fault or fail state is neither of these cases when computers show the brake fail most of the time, and every once in a while they don't show.

I once explained my experience with the start-up problem showing the Check Engine Light. That is this third case. To computers, it is the same faulty state as the sudden acceleration if you allow me to use this fault term. I considered it seriously, and brought my car to the dealer's attention only to be told that there were no problems in my cars as the on-board computer doesn't show any trace of the faults. Computers have no intelligence like us. Most of us will say the brake failure consistently unless we want to lie once we confirmed it. In the Computer Science field, they have tried to make computers imitating human intelligence. The field is called artificial intelligence. But usually such systems with human intelligence do not exist, and if they work in some limited situations, they are called expert systems. Computers don't know what they are doing. Garbage in garbage out.

I suspect the car's fault, probably the engine CPU or its software. Again such faulty states occur rarely, but they can. These days most high end cars have an electronic accelerator with no pedal connected to the throttle mechanically. The engine CPU controls the throttle as well as the fuel injection. Even if it's not faulty software, it could be a hardware glitch, either in the CPU memory or the pedal position sensors. If you estimate the soft memory or instruction error probability inside the CPU and multiply that by the number of cycles it is written or read per second, and factor in the number of hours the car is driven, you can see how often a wrong value could be sent to the throttle position servo. I bet most manufacturers don't have redundant or fault-tolerant software to catch this. Fault-tolerant computing starts from identifying faults to correct them. In my Check Engine Light at Start proves that such faults were not identified in my BMW. Some of you may still say that computers cannot be wrong. Yes, they are. Can you believe in some locations in the US, computers can break down more frequently? It is not the myth. Even radiation can change computer data. So NASA or military want their electronics radiation-hardened. There are more intense cosmic rays in space. Fault-tolerant systems result both from robust hardware and software designs.

I believe the black box should now be mandatory for cars so that faulty events can be recorded to clear up whose faults they are Ė car or driver. It will help with insurance, warranty, law suit, etc. And manufacturers can fix the bugs early before bad accidents happen. But they still should video-tape the motion of the drivers' foot together with other electronic info. Until then, this controversy will continue.

Thanks if you finished reading. Again happy driving.
Wit, I read your analysis of the potential failure modes of DBW systems. I assume English is not your first language because I had to work a little in spots to discern your meaning, but I think I got the gist of it.
I respectfully disagree with your conclusions. I don't have an EE background but I do have ME experience and a career in the automotive repair field. I'm also a long time member of the Society of Automotive Engineers. Recently I had a very intensive course dealing with DBW throttle control systems.
(DBW is used to replace mechanical and hydraulic components/controls on cars, trucks, aircraft-both civilian and military-and complex machines. It is currently under development for use in the braking system of automobiles.)
An automotive DBW system does NOT receive commands from the ECU (main engine management computer, also called the CPU and ECM and PCM). The throttle servo gets its command from the driver's foot and reacts to it and tells the ECU what it is doing. The main computer can only override that command/control system and shut it down. It cannot speed it up. In short, the foot commands, the throttle responds, the ECU is informed. All of these actions have built in redundancies and code strings which, in every case, result in system shutdown if any anomolies occur.
Can things go bad? Maybe. But no expert in the field has come up with a theory which stands up under controlled testing. Believe me, I'm no fan of DBW, but I do have an objective approach to problem solving and until I see empirical evidence to the contrary I have faith in them from a safety standpoint.
Automotive engineers have long dealt with electrostatic emission and stray electrical currents. Suffice to say that any critical system is suitably protected.

Last edited by DSXMachina; 11-08-2009 at 01:52 PM.
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  #46  
Old 11-08-2009, 03:30 PM
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KentW KentW is offline
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Originally Posted by Beenthere View Post
My belief is that people should learn how to drive properly and not receive a driver's license until they can demonstrate the ability to drive safely under all driving conditions.
Unfortunately, the hardest part of the road test for most people in this country is parallel parking. That's just sad.

If we wanted to do it right, they'd also have to pass a slalom and skidpad test.
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  #47  
Old 11-08-2009, 03:37 PM
pony_trekker pony_trekker is offline
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Originally Posted by wit3356 View Post
Yes, it was a sad story. I live in San Diego, and it was a big news. Even Toyota Chairman apologized in a press interview saying something like that customers buy Toyota for its safety, but he had a remorse that Toyota lost the confidence of the customers. They indirectly admitted that modern electronic cars can run away.

Back in the day, I had a foreign object fall into my carburetor locking it in the floored position. Back in the days with keys, it was very simple to turn the key off.

Last edited by pony_trekker; 11-08-2009 at 03:48 PM.
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  #48  
Old 11-08-2009, 03:43 PM
pony_trekker pony_trekker is offline
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Just an FYI, consumer reports did a test in the same exact car showing what should have been done. They took the car up to 80mph put a foot on the brake and then put the car into neutral. Our local news showed the video a couple days after the accident.

In general, I believe everyone should go to defensive driving school at some point because the BS driving tests they administer in the USA are just plain bogus.
http://abcnews.go.com/video/playerIndex?id=8980024

CR Engineer wiped out the brakes on a Toyota Venza while trying to brake while under full throttle.

Go to the last 10 seconds. German cars are engineered differently. Brake overrides accelerator.

Last edited by pony_trekker; 11-08-2009 at 03:53 PM.
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  #49  
Old 11-08-2009, 03:58 PM
wit3356 wit3356 is offline
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Thanks. I got your points. Let's not get emotional any further. Best wishes.
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  #50  
Old 11-08-2009, 05:32 PM
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DSXMachina DSXMachina is offline
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Thanks. I got your points. Let's not get emotional any further. Best wishes.
Hi wit, I think this discussion has been fairly civil. A lot of people have made their points and done so as best we can on a bulletin board. Sure, we invest a little emotion in our postings but overall this thread has kept to the point. None of us have all the facts, yet most of us learn a little as we go along. The points you made were well thought out whether we agree or not.
If you want to see real vitriol you can always take a peek at some of the PoliSci postings in Off Topic.
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