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I replaced my ABS assembly, now my car thinks that the brakes are always on.

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by suirPPrius123, Jun 27, 2019.

  1. suirPPrius123

    suirPPrius123 Junior Member

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    I replaced my ABS actuator and accumulator assembly on my 2010 Toyota Prius with the same exact part number from a used part I found on eBay.

    As soon as I finished the replacement, I started the car, and the car continuously thinks the brakes are applied at all times. This makes going into power ON, ignition OFF impossible (as far as I know). I suspect that the problem is that I have to reprogram the ABS ECU, but I read that if I bought exactly the same part # that I wouldn't have to replace the ECU.

    The brakes have been bled and operate just fine.

    Here are the codes:

    C1202 -Master Reservoir level malfuntion
    C1203 -ECM communication circuit
    C1336 -zero point calibration of deceleration sensor undone
    C1345 -linear solenoid valve offset learning undone
    C1392 -zero point calibration of stroke sensor undone

    Do you think that the problem is that the ECU needs reprogramming?
    How do I go about doing that? (I have techstream)
     
  2. tankyuong

    tankyuong Senior Member

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  3. ChapmanF

    ChapmanF Senior Member

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    It's not really "programming" it needs; just to learn a couple operating points, following the procedure in the manual. Most of the codes are about that.

    Not all of them. The level sensor code could be there if you forgot to make that last connection to the reservoir bottle sensor, and the ECM comm circuit code is kind of a wild card; how positive are you about the re-connections you made at the skid ECU?

    Not getting to ACC or ON because the brake seems depressed could be as simple as your adjustment of the pedal height and the pedal switch.
     
  4. Pluggo

    Pluggo Senior Member

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    First clear all the codes with your Techstream, then see which codes, if any, come right back again.
     
  5. ASRDogman

    ASRDogman Senior Member

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    Were you able to get the problems resolved?

     
  6. black_jmyntrn

    black_jmyntrn Senior Member

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    curious on this. happening now. now sure how to adjust the switch more meaning, it's pushed into the little circle housing with the little tabs for it to lock in place at any level. all of the way in. there is a small gap from the little nipple button to the contact tab on the pedal and not sure what to adjust. The button bracket doesn't appear to be adjustable.
     
  7. ChapmanF

    ChapmanF Senior Member

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    The long snoot on the switch should be positionable in the brown nut-looking thing:

    [​IMG]

    But I'd approach this carefully: it doesn't sound like that pedal switch was replaced, or the pedal, or the adjustment of the switch was changed. If the one thing in the story that's been changed is the brake actuator, I would first be double-checking that it got seated all the way down on the firewall, old gasket got removed, didn't get two gaskets stacked up there, etc., to make sure the pedal comes back up to the same position it came back to before. If there's something like that going on, then the switch really should still be in good adjustment once that gets fixed.
     
    #7 ChapmanF, Nov 10, 2022
    Last edited: Nov 10, 2022
  8. black_jmyntrn

    black_jmyntrn Senior Member

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    replaced the booster. all is flush that's for sure and after finding the proper pages I'm going to try to loosen the Clevis Lock Nut and adjust.
     
  9. black_jmyntrn

    black_jmyntrn Senior Member

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    does the prius have the rubber gromet? i never saw one i dont think on the ground and the 2015 we have doesnt have one yet some places it says a part number for the gromet for a prius?

    https://attachments.priuschat.com/attachment-files/2017/08/130828_2010_Toyota_Prius_Repair_Manual_-_maintenance_-_brakes_-_pedal.pdf

    i didnt touch the clevis lock as id rather not loosen the booster stuff and it stay as is from toyota. for now going to make my own grommet just so I can bleed the brakes and put wheels back on
     
  10. black_jmyntrn

    black_jmyntrn Senior Member

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    i ended up using some instamorph and created a gromet/rider/ it works now piece