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car stopped but rolling forward/backward and crack sound

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Yanathome, Apr 22, 2013.

  1. Yanathome

    Yanathome New Member

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    I am new to this forum. I have a 2008 Prius basic model bought second hand.
    There are two issues since I have bought the car; first it will roll back or forward when the brake applied, this happens on any uphill or downhill. I brought the car to Toyota service centre, they did a brake test, the test passed. but this doesn't resolve this issue.
    It just very wiered. during driving, all brake works ok, but parking the car, if not in even service, it starts to roll. anyone has similar problem??

    Second, recently I hear there's a crack sound when apply the brake during low speed, especially during the stop/start traffic, and I notice mostly happens when the electrical motor in running. So when brake, the crack, like the spark comes from somewhere like battery. While brake to slow down from high speed, seems no sound. So I suspect it was from the battery or electric motor. Again, any one experience similar situation.

    Much appreciate if you can give me some advice.
    Yanathome
     
    #1 Yanathome, Apr 22, 2013
  2. HTMLSpinnr

    HTMLSpinnr Super Moderator
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    **Mod Note** Moved to Gen II forum.
     
    #2 HTMLSpinnr, Apr 22, 2013
  3. Britprius

    Britprius Senior Member

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    Where in the world are you? As this affects the braking arrangement on the rear of the car. (discs and drums or just drums) When you say the car rolls on a hill is this in park?

    John (Britprius)
     
    #3 Britprius, Apr 22, 2013
  4. nh7o

    nh7o Off grid since 1980

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    I think that the parking pawl could be the problem here. There are two parking brakes: the usual manual brake that is engaged by the pedal, and the mechanical parking pawl, like in any automatic transmission. If the car rolls when turned off, then the parking pawl is definitely broken. If it rolls with the parking brake foot pedal applied, then that is an additional problem.
     
    #4 nh7o, Apr 22, 2013
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  5. Yanathome

    Yanathome New Member

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    guys, thanks for your response.
    I am in Melbourne, Australia.
    The car rolling back or forward about 1 inch or so after the foot pdeal applied. It doesn't matter whether the car is still on or not, as long as it parks on a slope surface, it will roll by 1 inch so, after that, like normal, I mean it feels park properly.
    Add one point, it appears only during the parking this brake has problems, during driving, slowing down all works normal.
     
    #5 Yanathome, Apr 22, 2013
  6. bobodaclown

    bobodaclown Member

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    It sounds like 2 separate problems.
    1. Parking brake needs adjusting. (brake system rear only cable adjustment)
    2. Parking pawl is getting worn (transmission electrically driven worn pin or hole)
     
    #6 bobodaclown, Apr 22, 2013
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  7. nh7o

    nh7o Off grid since 1980

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    I think this is normal. If I am on a slope, and apply the parking foot brake, it will move a bit. Without using the foot brake, and just using the P button, then there will be a distinct amount of rolling until the parking pawl catches. There is play in that mechanism.

    If I am stopped on a steep hill, I use the parking foot brake first and push quite hard, then take my foot off the main brake pedal, let the car roll its little bit, then go into P on the transmission. This way the parking pawl has the least amount of force on it.
     
    #7 nh7o, Apr 22, 2013
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  8. Yanathome

    Yanathome New Member

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    Thanks again. This is the first automatic car I drive. I don't feel unsafe, as I know after roll one inch so (either way), it parks solid. but just this uncomfortable feeling. I'll mention this parking pawl when I take it to do its service this year.
    I have another issue with the car, I'll post another topic see if any ideas. If you have chance, could you please have a look and see if can shed some lights on it?
    Thanks and all the best!
    Yanathome
     
    #8 Yanathome, Apr 23, 2013
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  9. Britprius

    Britprius Senior Member

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    Living in Australia your rear brakes are different to the US brakes.

    Your brakes are the same as mine in the UK. Do not adjust the brake cable.

    The rear brakes are adjusted by taking the rear wheels off the car (one at a time) and with the car in park but with the parking brake off you can adjust the parking brake by removing the rubber plug just outside the wheel studs and turning the star wheel with a flat bladed screw driver till the wheel disc locks then turn back till the wheel disc just rotates freely.

    The star wheel is located at a position just a little forward of the whole being at the bottom of it's rotation (7 oclock passengers side, 5 oclock drivers side).

    John (Britprius)
     
    #9 Britprius, Apr 25, 2013
  10. uart

    uart Senior Member

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    Hi Yanathome. We really need to work out whether your problem is in the park brake, or if it's in the transmission park mechanism. These are two completely different things, and it's important that you understand the difference. (So if you don't understand the difference please ask ok :) ).

    To test if there's a problem with the actual park brake then please do the following tests. These will take the transmission park mechanism completely out of the equation.

    - Park on a moderate hill with the car facing downhill.

    - While keeping your right foot on the regular foot brake, move the transmission selector to "N" and hold it for a few seconds until you see it has shifted to "N" on the dash display.

    - Press very firmly on the park brake with your left foot, you should feel it ratchet down and apply the brake.

    - Now gently release the normal brake with your right foot and note if it moves and if so how far.

    - Move the car so that it's pointing uphill and repeat all of the above steps. Again note (if/how far) it moves.

    Report back here on the results ok. :)

    BTW. Make sure you release the parkbrake before moving the car. To release the park brake just press it firmly a second time (again with the left foot) and you should feel the ratchet release. I know I shouldn't really need to say all that, but you do sound like you're pretty unfamiliar with the Prius. :rolleyes:
     
    #10 uart, Apr 26, 2013
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