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Unintended Acceleration -- While Parking

Discussion in 'Gen 3 Prius Main Forum' started by evpv, Dec 29, 2010.

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  1. evpv

    evpv Active Member

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    I asked yesterday if you read the complaints. If you haven't, open your mind up just a little and take a few minutes to read what dozens of Prius owners said about the bumpy surface problem. Most of them described unintended acceleration while braking over bumpy surfaces, not just loss of brake force.

    https://www-odi.nhtsa.dot.gov/complaints/index.cfm

    Step 1: Vehicle--> Search Selected Type
    Step 2: Year-->2010-->Submit Year
    Step 3: Select Make-->Toyota-->Submit Make
    Step 4: Select Model-->Prius-->Submit Model
    Step 5: Select Component-->Vehicle Speed Control-->Click "Select this box if you would like to see a full summary" -->Submit
     
  2. bisco

    bisco cookie crumbler

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    it feels like u/a because of the change in braking. it's not linear like standard brakes without regen. we've all experienced it. it can make your heart stop for a millisecond, but, it isn't dangerous.
     
  3. 32kcolors

    32kcolors Senior Member

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    We don't need to read them because a lot of us have experienced this "momentarily loss of braking power" and it does feel like unintended acceleration to our brain. However, this is mostly perceived. Bob Wilson has measured this and concluded there's no measurable acceleration (at least according to the limitation of his equipments) after applying the 3rd generation brake fix. I take it you haven't experienced this yourself before or after applying the brake campaign. It was more scary before the brake fix and despite Bob's data, still feels like the car accelerates momentarily between regen to fiction transition but shorter in duration.

    It's mostly psychological and can be likened to what you expect when you step on the gas pedal and you thought the car was on but wasn't. Your body naturally leans forward expecting the car to move.
     
  4. jhinsc

    jhinsc Senior Member

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    Beyond the floor-mat issue and the software glitch that's been rectified, no one has found ANY evidence that will shed light on the UA problem, other than driver error. The black boxes records all events taking place in the Prius - why hasn't it recorded anything that will support driver's who claim they were pressing on the brakes, but in actuality their foot was firmly planted on the accelerator pedal? Point me to hard evidence and only then will I give any kind of credence to these stories.

    The story about the gentleman who ran over his wife and dragged her 130 feet, killing her in the process tells me this man should not have been allowed to drive in the first place. Let's face it - there are a lot of people who shouldn't be allowed to drive!
     
  5. xs650

    xs650 Senior Member

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    It's lot of stuff like this
    Most likely, the driver stepped on the throttle and thought he stepped on the brakes.

    Typical cockpit error.

    If you have something conclusive that can't be explained by a short circuit between the drivers ears, please post it. I'm not going to wade through dozens of sloppy sudden acceleration/brake failure reports or UFO abduction reports.
     
  6. Ruff Rider

    Ruff Rider New Member

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    After reading 11 pages, I'm sticking to my Schwinn Stingray bike. Damn that reminds me...I need new brakes on my bike:pound:
     
  7. evpv

    evpv Active Member

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    So this doesn't sound dangerous to you?

    "NEW 2010 PRIUS COMMUTER CAR SUDDENLY ACCELERATES OR SCOOTS WHEN BOTH FEET ARE ON THE BRAKE. THE VEHICLE TAKES THE SAME ROUTE TO AND FROM WORK DAILY. ON EVERY TRIP, WHEN THE RIGHT FRONT WHEEL PASSES OVER A RECESSED MANHOLE, THE VEHICLE ACCELERATES. I IMMEDIATELY PUSH HARDER ON THE BRAKE TO STOP THE VEHICLE. THE MANHOLE IS ABOUT 30 FEET IN FRONT OF AN INTERSECTION, SO I AM ALREADY DECELERATING AND BRAKING WHEN I CROSS OVER THE MANHOLE. THIS IS SCARY BECAUSE, IF THE CAR DOESN'T STOP, IT WILL TAKE ME OUT INTO THE MIDDLE OF THE INTERSECTION. BOTH FEET ARE ON THE BRAKE. I HAVE DRIVEN FOR OVER 40 YEARS, AND THIS THE STRANGEST THING I HAVE EVER EXPERIENCED."
     
  8. evpv

    evpv Active Member

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    If the computer has a glitch big enough to apply throttle while the owner is applying the brakes, will the black box record the brakes being applied, the throttle being applied, or both being applied? Maybe Toyota should enlist the help of the experts at NASA to figure this out.
     
  9. Ruff Rider

    Ruff Rider New Member

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    Need I say more? :rolleyes:
     
  10. 32kcolors

    32kcolors Senior Member

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    This is the typical perceived loss of braking power when going over a pothole that feels like UA to a lot of us, but yes, this sounds dangerous because both feet are on the brake (you could easily catch the gas pedal that way) and we're dealing with an elderly driver (over 40 years of
    driving experience).

    Do yourself a favor and go over a few potholes to see for yourself. The brake fix doesn't eliminate it completely.
     
  11. evpv

    evpv Active Member

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    Your quote isn't even from the Vehicle Speed Control section.

    I'm surprised that a lot you are not even willing to read the complaints. Seems pretty closed minded to me.
     
  12. evpv

    evpv Active Member

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    Over 40 years of driving experience means the guy could only be 56 years old. Is that too old to be a safe and competent driver?

    Here's another, safe or unsafe?:

    "MY 2010 TOYOTA PRIUS LOSES BRAKING ABILITY AND LUNGES FORWARD WHILE BRAKING ON ANY UNEVEN SURFACE I.E. POTHOLE, MANHOLE COVER, BUMP METAL PLATE OR STRIP, ETC... THIS HAS LEAD TO SEVERAL NEAR MISS COLLISIONS AND DUE TO THE AMOUNT OF TIME I SPEND IN THE CAR HAPPENS AN AVERAGE OF 3 TIMES PER DAY. BECAUSE I FEAR FOR MY OWN SAFETY I DO NOT ALLOW PASSENGERS IN MY CAR AND I WILL NOT LET ANYONE ELSE DRIVE MY CAR. I'VE HAD TO ADJUST MY DRIVING TO TRY AND COMPENSATE FOR NO BRAKING ABILITY AT ANY GIVEN TIME. I HAVE NOW REPORTED THIS PROBLEM TO MY DEALER TOYOTA OF MERRILLVILLE IN PERSON 3 TIMES AND OVER THE PHONE ON SEVERAL OCCASIONS AND EACH TIME I WAS TOLD THEY WERE UNABLE TO DUPLICATE THE PROBLEM AND THEREFORE THERE WAS NO FIX THEY COULD OFFER. THEY ALSO TELL ME THAT I AM THE ONLY CUSTOMER REPORTING THIS TYPE OF CONCERN BUT I HAVE BEEN ABLE TO CONNECT WITH MANY PRIUS OWNERS EXPERIENCING THIS LOSS OF BRAKING WHILE OVER UNEVEN PAVEMENT. I BELIEVE TOYOTA IS DOWNPLAYING THIS PROBLEM AT THE RISK OF PUBLIC SAFETY."
     
  13. xs650

    xs650 Senior Member

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    The driver sounds dangerous and like he is greatly exaggerating a well know characteristic of the brakes.

    The is no solid evidence of a problem and there are relatively common driver errors that cover what has been reported. The event in the report you are quoting has been duplicated and reported by others without the hyperbole. It's not a problem for a competent driver.
     
  14. wick1ert

    wick1ert Senior Member

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    This is the same issue as the last one you posted. The brake software update. The car doesn't "lunge" or lose braking ability. This is the transition from regen to friction that was mentioned before. Personally, I think that if that extra distance means you were going to slam into the car in front of you, you weren't allowing a proper following distance and you were waiting too long to apply the brakes initially. I do believe that before the update, the cutout was a little disconcerting when it first happened, but a good driver will understand how their vehicle reacts to different conditions and adjust their driving style to match those conditions.
     
  15. DataWrangler

    DataWrangler Prius Owner (finally!)

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  16. 32kcolors

    32kcolors Senior Member

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    He falls in the group of ages more likely to report UA than younger groups. Whether the age is considered safe and competent to drive is irrelevant. As another poster said, don't become a statistics.

    I've experienced a few scary incidents before applying the brake fix, but the near miss collisions are an exaggeration. The car will stop sooner when you apply the brake harder.
     
  17. Ruff Rider

    Ruff Rider New Member

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    "MY 2010 TOYOTA PRIUS LOSES BRAKING ABILITY AND LUNGES FORWARD WHILE BRAKING ON ANY UNEVEN SURFACE I.E. POTHOLE, MANHOLE COVER, BUMP METAL PLATE OR STRIP, ETC... THIS HAS LEAD TO SEVERAL NEAR MISS COLLITIMES PER DAYSIONS AND DUE TO THE AMOUNT OF TIME I SPEND IN THE CAR HAPPENS AN AVERAGE OF 3 . BECAUSE I FEAR FOR MY OWN SAFETY I DO NOT ALLOW PASSENGERS IN MY CAR AND I WILL NOT LET ANYONE ELSE DRIVE MY CAR. I'VE HAD TO ADJUST MY DRIVING TO TRY AND COMPENSATE FOR NO BRAKING ABILITY AT ANY GIVEN TIME. I HAVE NOW REPORTED THIS PROBLEM TO MY DEALER TOYOTA OF MERRILLVILLE IN PERSON 3 TIMES AND OVER THE PHONE ON SEVERAL OCCASIONS AND EACH TIME I WAS TOLD THEY WERE UNABLE TO DUPLICATE THE PROBLEM AND THEREFORE THERE WAS NO FIX THEY COULD OFFER. THEY ALSO TELL ME THAT I AM THE ONLY CUSTOMER REPORTING THIS TYPE OF CONCERN BUT I HAVE BEEN ABLE TO CONNECT WITH MANY PRIUS OWNERS EXPERIENCING THIS LOSS OF BRAKING WHILE OVER UNEVEN PAVEMENT. I BELIEVE TOYOTA IS DOWNPLAYING THIS PROBLEM AT THE RISK OF PUBLIC SAFETY."

    Look if this person can make this happen "an average of three times a day" why would he,she not take a Toyota tech for a ride?

    My brakes were squeaking on my truck. Took it in to get fixed. Dealer called and said they could not make the brakes make any noise. I went down and took the Tech out for a ride. Two minutes later we were back at the dealership and the tech fixed my truck. They were putting the brakes on to hard. Replaces the pad all better now.

    Moral of the story.....If you can make it happen then take a tech for a ride.
     
  18. evpv

    evpv Active Member

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    Here's what you can expect to receive from Toyota if this ever happens to you:

    http://www-odi.nhtsa.dot.gov/acms/d...Correspondence/2010/EVOQ/EQ-10350746-6991.pdf
     
  19. evpv

    evpv Active Member

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    Total US Population: 310,554,000
    People killed during 9/11 attack: 2,983
    Deaths as percent of population: 0.001%

    Your point?

    Percentages are great until the problem happens to you or a loved one.
     
  20. evpv

    evpv Active Member

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    Apparently true, because the one guy resorted to using both feet to stop the car after it glitched while stopping for the same intersection several times. Sounds perfectly safe and logical to me. And as Toyota said... they tested the car and didn't find any problems, it could be driver error.
     
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