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What happens if the P button is pushed while in motion/B drive?

Discussion in 'Gen 2 Prius Technical Discussion' started by prius530, Aug 17, 2007.

  1. prius530

    prius530 Junior Member

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    Sorry if this is a repeat question, but what would happen if the park button is pushed while the vehicle is driving? Would the transmissions be ruined or is there intelligent software to prevent a mishap like this? It seems there are so many buttons on the dash that I could actually touch the park button by accident while driving while doing something else. Of course with a regular transmission it is more of a deliberate effort to do so and is very unlikely.

    Also if I use the B drive to go downhill is there any limit to how fast or how long the vehicle is in B drive without breaking something? Everytime I hear a high pitched whine from a transmission I think something is going to break soon.
     
  2. bgdrewsif

    bgdrewsif New Member

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    I have wondered about the P button in motion too... anyone have an answer / been brave enough to find out?
     
  3. IsrAmeriPrius

    IsrAmeriPrius Progressive Member

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    Why don't you guys give it a try and report on the results of your experiments?

    B)
     
  4. aaf709

    aaf709 Ravenpaw of ThunderClan

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    What happens is that the body, plus seats, with rip off the frame. The frame will stop and the body will continue forward for several feet. A special sound chip will play the "wha wha wha" sound and you should also hear some canned laughter.

    Seriously, the car has safety features to prevent anything bad from happening, although if you're going less than 3mph something may happen.
     
  5. ceric

    ceric New Member

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    I think if the speed is faster than 3-5mph, the Prius goes into 'N' after you push the 'P'.
    When it is slower, it actually goes into 'P'.
     
  6. V8Cobrakid

    V8Cobrakid Green Handyman

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    P is a parking pin. A pin!. it also drops in around 5mph. I've dont his. it feels like you hit a wall. the pin drops in and the car jurks franticly... first it stops then bounces back.. then forward till it settles.

    i sucks.. don't try it. if you ever do it on accident, you'll never do it again.
     
  7. hobbit

    hobbit Senior Member

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    Actually the cutoff is about 2 mph, not 5. I went out and tested
    this in the slipperiest snow I could find, such that if the pawl
    locked the wheels would just harmlessly slide. Attempts to park,
    or drive in the direction opposite current direction of travel, all
    invoke the "beep beep" and the system just falls to Neutral.
    .
    Still, the parking lurch if you do manage to hit it while rolling
    a little bit is pretty profound. Don't do that a lot, since it
    still puts a lot of stress on things.
    .
    _H*
     
  8. Bear68

    Bear68 Member

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    You can actually leave a Prius in B for as long as you like. What happens is the computer "full fields" the generator into producing the maximum output of electricity which has the effect of putting maximum draw on the source of the turning force. I.E. the spinning wheels. When you hit the gas, the computer automatically switches back to normal drive and uses that regenerated power. Using B simply slows the car much faster when you let off the gas without having to use the brakes.It will not cause any excessive wear or tear.

    Hitting the park button while rolling is not a very good idea. The system has safeguards, but it still relies on a mechanical part which moves to lock the car in park. Stop first, then hit park. B)
     
  9. rudiger

    rudiger Active Member

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    Does the speedometer actually indicate 1 or 2 mph when the parking pawl engages? If so, it seems quite odd. I would have thought the system would not allow the pawl to engage at all unless the system said the vehicle was completely stationary.

    I can't think of any reason for it engage with the vehicle in motion (even a very slight amount) unless there is some slight delay between the signal and the time the vehicle actually is (or is not) in motion.
     
  10. qbee42

    qbee42 My other car is a boat

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    The Prius always reverts to a safe setting if you push something stupid, most just switch into N. If you hold down the Power button it will shut off the car, which could be useful in an emergency.

    B mode is never needed unless you drive down long or very steep roads, such as mountain driving. B mode causes engine braking to occur, which throws away energy instead of putting it into the battery. Regen braking also occurs, but you start right off with engine braking. This is only useful in a situation where the battery is going to max out before you get to the end of the hill, so it will help save the friction brakes.

    Tom
     
  11. FL_Prius_Driver

    FL_Prius_Driver Senior Member

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    <div class='quotetop'>QUOTE(rudiger @ Aug 19 2007, 12:52 AM) [snapback]498558[/snapback]</div>
    With the car in gear, but the brake not pushed, the car creeps forward at a couple of MPH. Placing the car in park in this condition makes sense for safety reasons. I once got out of the Prius in this condition (stupid, but true) and the last ditch effort to recover requires the hands to hit something like the power or park button.
     
  12. rigormortis

    rigormortis Active Member

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    this was on mythbusters last week.
    automatic transmissions protect the transmission and if you pressed the park button
    while the vehicle was in motion (over a certain speed) it would most likely beep and ignore you