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Toyota recall

Can my Toyota Avalon be retro-fitted with a brake override system? I don’t think the pedal is the problem–personal opinion.

With enough money, you can do almost anything. What exactly do you mean by a “brake override system”?

Why do you not think it is a pedal problem?

Think it is something else since I keep hearing pedal on the cars was not actually stuck. Man talked to on news at dealership (he had coasted in in N) said he and repaid dept. knew pedal was not stuck.

Brake override system to disengage motor when brake is applied.

Okay, so you don’t trust the electronics/software that run the engine to kill the throttle if the gas pedal is not depressed, but you would trust some rushed out additional software to kill the throttle if the brake pedal is depressed?
The brake override software is there only to protect against a stuck gas pedal, the thing that you do not believe is happening.

In answer to you actual question, yes it can if Toyota decides to release new software for it. No hardware would have to be added, you would just get the dealer to download new software (aka firmware) to the PCM.

I did not say I would trust something “rushed out” to fix the problem; and if it would not help the problem if it were something to do with the electronic system, then there would not be any point in it. However, you must not think they are “rushing out” their metal shim “fix.” What about recalling because of floor mats and then the people that were killed right after Christmas had the floor mats in the trunk–they thought they were safe.

Brake override system can be incorporated, but you would lose your engine braking with the result that your brakes would wear out more rapidly and on a steep downhill stretch in the mountains, your brakes might fail. Those are the tradeoffs.

There are numerous rumors going around as to what actually is the cause(s), and Toyota will come up with the right fix; they have the most at stake! You will soon learn what the fix is and what the problem was.

News people are paid to produce “news”, whether that’s factual or not does not matter, as long as it sells papers and gets viewers.

These people were safe, if they had just shifted to neutral.
All sorts of emergencies can happen in any car. You have to prepare for it and not panic.

Personally, I’m no fan of Toyota at all, but I believe them about the sticking pedal. Too much effort has gone into the failsafe design of the electronics and the software to believe that it could be the problem.
When it’s said and done, you will find that at least half of these Toyota sudden acceleration/stuck pedal cases are false. Some will be people who hit the gas instead of the brake. Some will be people who had a wreck and decide to blame this for it instead of taking responsibility for their own mistakes. Some will be people who see $$$ and make up something to try an take Toyota to the cleaners. And lastly, some will be real stuck pedal issues. Even some of those with stuck pedals are going to think that it was something else.

You do raise a good point, many other makes with ‘drive by wire’ systems have them programmed to cut the throttle when the brake is pushed, but Toyota doesn’t. I have not read that they’ll be revising any existing cars’ programming, and I would not trust this to somebody else.

Toyota has not mentioned revising programming and media suggests pedal fix (shim) is all that is going to be done for cars already on the road. All GM models have a brake override system some other manf. put them on some models. I don’t know about Ford. I had a LeSabre and will probably go back to GM when I feel like I can trade this one in and get a reasonable trade-in value.

My Lincolns are throttle by wire, and they don’t have brake override.

Yes, it’s not all. According to Car and Driver: “Since the advent of electronic throttle control, many automakers have added software to program the throttle to close?and therefore cut power?when the brakes are applied. Cars from BMW, Chrysler, Nissan/Infiniti, Porsche, and Volkswagen/Audi have this feature”

No individual mechanic, independent shop, or dealership mechanic would even attempt to engineer something like this because too many of the general public are lawsuit happy.
Let a crash occur due to something not even related to any kind of override and attorneys will be at the courthouse anyway.

I also agree with tardis that a number of stuck throttle incidents are likely caused by the driver rather than the car and the driver (in panic) will either genuinely not remember it was their fault or will remember it and point the finger elsewhere.

Nothing is going to be rushed out. Toyota would just have to fix everything twice - at twice the expense. And before they can bring their plan to the public, Toyota has to convince the NHTSA that the repair will work. The NHTSA’s main concern is citizen safety. When they accept Toyota’s plan, it will be brought to the affected owners.

The throttle on an engine has a somewhat strong return spring that requires a constant pressure while driving. Even today’s ‘fly-by-wire’ throttle has a heavy spring at the engine, but the accelerator pedal is not connected to the throttle, only to a potentiaometer (like a light brightener/dimmer). A very light spring will pull the potentiometer back to dead idle but resistance is needed to give the right feel to the driver. A heavy spring can be fatigueing. In their effort to make driving more pleasurable the engineers used a very weak return spring and a friction drag to give resistance to pressing the pedal but minimum pressure to hold the throttle at a constant speed. As the return spring weakens with use and the friction pads get dirty and gummed up the pedal is slow to jump back to idle. A heavier spring would be an instant and positive repair, but then there’s the fatigue issue. I certainly don’t work for Toyota and my opinion is just from observations of the fly-by-wire mechanisms on several cars. I am looking forward to seeing a repaired Toyota.

I posted that same C&D thing on another thread. It seems a lot of people think the brake over-ride shuts off the engine, or something. C&D says it just sets the throttle to minimum.

On another thread, someone said we two-footers would become extinct, which is utter nonsense. Two footers are supposed to let off on the throttle when they use the brakes, just like everyone else. Tom and Ray said this nonsense several years ago. They apparently know some poor chap in his late 80’s who barely passes the vision test, and drives around with both feet to the floor, and conclude all two footers do the same thing.

If anything, brake over-ride will help clean up the bad two footers, who will suddenly find their cars shutting off the throttle if they do ride the brakes.

Sounds like it’s a good deal all around.

By the way, Doc, on my Sienna, I use engine braking here in the mountains all the time, and do not understand why brake/throttle over-ride will reduce engine braking? I normally have the throttle at minimum when I have down-shifted for engine braking. Still, you know I rate you highly, and wonder if you can explain why brake/throttle over-ride will change that?

We are told: "Simply brake with 2 feet, put the car into neutral then turn the engine off."
MAY NOT BE SO SIMPLE! Watch these video clips:

TESTIMONY OF TOYOTA DRIVER WHO ‘LOST ALL CONTROL’
(after putting car in neutral and unable to turn off engine!!!)
http://news.bbc.co.uk/2/hi/business/8533129.stm

and

"IS TOYOTA’S SOFTWARE TO BLAME FOR SAFETY PROBLEMS"
http://news.bbc.co.uk/2/hi/science/nature/8535477.stm

and the CA crash:
“911 Call Released from Crash that Prompted Initial Toyota/Lexus Floor Mat Recall”
(with California Highway Patrolman driving unable to stop vehicle)
http://www.cardealerreviews.org/?p=247148

"Witnesses saw flames coming from the front and rear tires of the speeding 2009 Lexus ES 350 before it crashed Aug. 28 in Santee, suggesting ?long, constant heavy braking,? said Sgt. Scott Hill, the lead sheriff’s investigator. "

"Toyota Recalls Spur Worries"
http://www.npr.org/templates/story/story.php?storyId=123341958

An added brake override may or may not need added hardware. The ECU would need a signal telling it the brakes have been applied. The signal could be taken from the BCM, using the same signal that lights the brakelights, or could involve and added sensor or connection at the brake pedal lever.