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changing brakes, car won't start

Discussion in 'Gen 2 Prius Main Forum' started by chirobeero, Dec 27, 2017.

  1. chirobeero

    chirobeero New Member

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    hey guys, just changed my brakes on my 04 prius and i forgot to turn off the 12v battery. The car turned on midway through changing my brakes. i finished putting the brakes on and there is good pressure in the brakes. But now the car won't start, the car doors won't even unlock. Any ideas?
     
    #1 chirobeero, Dec 27, 2017
  2. Dxta

    Dxta Senior Member

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    Try unhooking the terminal cable of the 12volt battery, and see what happens.

    Did you temper with the hydraulic system (brake fluid leaked out)?

    Does the dashboard lights all power up? If it doesn't, get another battery to try em out.
     
    #2 Dxta, Dec 27, 2017
  3. chirobeero

    chirobeero New Member

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    I did clamp the brake line before I changed the caliper and a bit did leak out. put more brake fluid in and the brakes seem to be pumping fine. the dash doesn't turn on at all, does the 12v battery need to be replaced or the big expensive one?
     
    #3 chirobeero, Dec 27, 2017
  4. valde3

    valde3 Senior Member

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    Why do you think that you need to replace either of the batteries? What does and what does not work? What happens when you try to start it? If nothing works then check the 12V battery if it’s empty charge or replace it.

    You should have disabled brake system when doing brake work.
     
    #4 valde3, Dec 27, 2017
  5. chirobeero

    chirobeero New Member

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    I am trying to jump the car from the back and I'm not sure where to connect the cables to the 12V battery. I can't get a car next to it to jump frmo under the hood.
     
    #5 chirobeero, Dec 27, 2017
  6. bisco

    bisco cookie crumbler

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    connect to the terminal posts, positive first. don't start the engine on the donor car.

    what would make the car turn on while you were working on the brakes?
     
    #6 bisco, Dec 27, 2017
  7. SFO

    SFO Senior Member

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    Time to test the 12v battery with a voltmeter, or take it to an auto parts chain and have it tested for free.

    If this 12v battery gave up the ghost while preforming a one (1) to three (3) hour brake service it might be time for a new one, when was the last time it was replaced?
     
    #7 SFO, Dec 27, 2017
    Raytheeagle likes this.
  8. Dxta

    Dxta Senior Member

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    Did you bleed the rear brakes after the fluid leaked out?

    I mean the 12V battery, and not the traction battery. Try another 12volt battery and see how it goes.
     
    #8 Dxta, Dec 27, 2017
  9. Dxta

    Dxta Senior Member

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    I just hope he hasn't done treble damage on the electronics of the car?

    Toyota specifically states to remove the two abs motor relays, whilst working on the rear brakes hydraulic system.
     
    #9 Dxta, Dec 27, 2017
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