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?

     
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