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Has ANYONE here had an Accelerator, Steering or Braking Problem?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by ukr2, Mar 10, 2010.

  1. ml194152

    ml194152 Member

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    Re: Has ANYONE here had an Accelerator, Stearing or Braking Problem?

    Yeah, you have a 2010 with the adaptive cruise control. When you passed the car ahead of you the cruise control saw there were no cars ahead and proceeded to accellerate to the speed you set it at, probably 90+ MPH.
     
  2. paulemus

    paulemus New Member

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    Re: Has ANYONE here had an Accelerator, Stearing or Braking Problem?

    A lot of people fly in a lot more complicated airplanes. The big difference is you can't pull an airplane over to the side of the road.
     
  3. Evilshin

    Evilshin Member

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    Re: Has ANYONE here had an Accelerator, Stearing or Braking Problem?

    David, the cause of your problem is the regen brakes, while not dangerous, it can seem quite disconcerting. What is happening is: while you are holding down your brakes, the computer applies regen as well as power brakes. (The mechanical hydraulic part of the brakes will apply as per usual.) But the power augmented hydraulic part of the brakes will be attenuated to allow the regenerative braking force from MG2 to be applied.

    Regen braking is similar to running a motor backwards. But unlike powering the motor backwards, (commonly known as plugging a motor) regenerative mode does not apply power to slow down. Instead it just saps power from the field coils (the electromagnets in MG2's stator) to charge the batteries. This power is generated by the motion of MG2's rotor, which is a rotating permanent magnet in braking situations. As power is sapped from the stator coils, motion is sapped from the motor, and the car. Power is only generated when the car is moving, and is proportional to the speed of the car.

    Now if you hit a bump, the front wheels might instantaneously slow down. This causes the regen forces to instantaneously drop for a given regen setting. The computer can't compensate with higher regen brake level or higher power brake level fast enough. The result is the feeling of the the brakes "giving" when you hit a pot hole while braking.

    It really is normal.

    As for my car, that regen give bump is the only strange behaviour that my prius has ever experienced.
     
  4. duffasaurus

    duffasaurus Senior Member

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    Re: Has ANYONE here had an Accelerator, Stearing or Braking Problem?

    I have a 2007 Prius and recently traded my 2009 for a 2010 V/AT. Never experienced a single problem with any of them. In the 2010, I feel safer at any speed, in any weather condition then in any of the previous model years I have owned!
     
  5. Jolly Paul

    Jolly Paul Member

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    Re: Has ANYONE here had an Accelerator, Stearing or Braking Problem?


    Geraldo Rivera: "What have the families of the many people tragically killed by your dash rattle said to you? Do you feel Toyota killed these people deliberately or out of negligence?" :rolleyes:
     
  6. zenMachine

    zenMachine Just another Onionhead

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    Re: Has ANYONE here had an Accelerator, Stearing or Braking Problem?

    The first day I drove my Prius it veered left all of a sudden, hit the pavement and one of the plastic rings fell out (which I didn't know until we got home.) I got scolded by my wife for bad driving. But I later learned (from the good folks here) that the Prius alignment on new cars can be a little bit off.

    Other than that (and a really bad "premium" stereo), no problems whatsoever.
     
  7. Tideland Prius

    Tideland Prius Moderator of the North
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    *Moved to Troubleshooting Forum*
     
  8. drash

    drash Senior Member

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    Yeah, when I first had my 2005 for about a week and we had snow one day I applied the brakes and slid for quite a bit. Bought snows the following winter and had no more problems.

    On a side note, I've had my headlights on since I picked it up day before Thanksgiving, 2004 (helps with other driver's acceleration, braking and/or steering problems). My insurance agent thinks I have DRL and I get a discount for it. I've never replaced a light, anybody think I'll have a problem?
     
  9. ukr2

    ukr2 Senior Member

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    Re: Has ANYONE here had an Accelerator, Stearing or Braking Problem?

    a1a1a1 stated:

    Yes, and it's no bull. Same scenario, went to pass with cruise enabled and the car continued accelerating. It snapped out of it after several seconds, after the driver started pumping switches, controls, brakes, accelerator on and off, but not without giving the driver a good startle. The freeway was moving but lots of other cars. Another second and there would have been an accident.
    ===================================================================

    a1a1a1,

    Who was the driver? Were you in the car? How long ago did it happen?
     
  10. ukr2

    ukr2 Senior Member

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    Mr. Moderator,

    I see you Moved my Thread:
    This is a discussion on Has ANYONE here had an Accelerator, Steering or Braking Problem? within the Gen III 2010 Prius Care, Maintenance and Troubleshooting forums, part of the Gen III (2010+) Toyota Prius Forums category.

    However, I have a 2007 Gen 2 and with all the Media attention, I wanted to know if ANY Gen 1, 2 or 3 have any of the reported problems.

    Please move the Thread back to Prius and Hybrid News

    Thanks,
     
  11. speakchucker

    speakchucker Junior Member

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  12. speakchucker

    speakchucker Junior Member

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    Re: Has ANYONE here had an Accelerator, Stearing or Braking Problem?

    Was "the driver" you? Were you with them when it happened? I'm very curious which switches were "pumped" because the driver should simply have applied the brake, unless you're saying the brakes failed as well. Using complete sentences might help here too.

    One thing I find in common with all of these anecdotal stories is how sloppily and ambiguously they're conveyed. If the brakes did NOT turn off the cruise control and did NOT brake the car, it's interesting nobody actually says that they 1) did that first and 2) it failed and 3) the nature of that failure.

    This is a really simple if-then sequence folks, not rocket science.

    It's pretty clear the Big 3 have seen the Prius as a threat, but instead of these faux-grass-roots mud slinging, rumor and the-stupidest-driver-ever campaigns they might just try building a better car. This says something very compelling about our society, and we can't continue like this.
     
  13. Lloyd9

    Lloyd9 Junior Member

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    30k on my 08 touring, no issues with braking, steering or accelerator.
    I have experienced the anti-lock brake split-second change during 'wash-board' type bumps, and my wife indicated that she once experienced 'no brakes' when she came upon a speed bump too quickly (probably braking just before lift-off).
    But nothing lasting longer than a split second. Love the car, hate the bad media.
     
  14. bambi

    bambi New Member

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    I have an 05 Prius with 120,000 miles. The only braking glitch I notice is OCCASIONALLY (once every 6 months maybe) at speeds under 5mph, if I go over a speed bump or irregularity that causes one wheel to go faster than the other, the traction control will kick in for an instant, which disables the regenerative braking. So if I am coasting with a very light foot on the brake, it will feel like the regen has dissapeared for an instant. Similar to what you would experience if you were to brake on a wet surface and go over the slippery paint that they use for crosswalks and stoplight markings. But only at low speeds, and never a big enough issue to even think about a trip to the dealership. I love that car!
     
  15. lenjack

    lenjack Active Member

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    No. not on my '07 or my '10.
     
  16. smasho

    smasho New Member

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    Yes, as a matter of fact, I have had brake problems. Two years ago the stroke sensor failed and had to be replaced. This $400 part tells the computer how far one has depressed the brake pedal.

    This caused several warning lights to come on. The ABS system was non-functional and if I remember right, there was no regen.

    I did, however, have plenty of braking power. So much it was difficult to drive smoothly to the dealer. It was very difficult to lightly apply the brakes.

    After 50k in a Gen I and now 95k in a Gen II this was the only serious problem I've ever had. No car's perfect but that's what I call dependable.