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4 questions about ABS issue

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Kapcreations, May 31, 2024.

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  1. Kapcreations

    Kapcreations New Member

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    Location:
    Phoenix, USA
    Vehicle:
    2006 Prius
    Model:
    N/A
    Purchased new to me 2nd Gen Prius with 122K and newer main battery.


    No lights on dash, but prior owner stated daughter braked a few weeks ago and it hesitated.


    Purchased the car for a steep discount.

    While driving home, tapped brakes at light and ABS light popped up for a half second and went away.

    Hooked up my Autel at home and found 2 codes that were current, not historical.

    Tried resetting, power cycling car and clearing codes. Remained current.

    C1253, Current, Hydro-booster pump motor relay.

    C1256, Current, Accumulator pressure low.

    At first I thought maybe the pump or accumulator was going out.

    Went to AutoZone. Purchased Duralast Relay 19283, Part #19283, SKU #953394.

    Swapped it out with the old ABS No. 1 relay located in hood relay box, far bottom right relay position.

    Both trouble codes immediately went away.

    Took the car out for a test drive, testing various different speeds and braking.

    No issues.

    Went 50 mph and slammed on the brakes, and the tires locked and skidded; ABS did not kick in.

    There are still no trouble codes.
    1. Is that normal/expected behavior ?
    2. Why did ABS not kick in, provided no codes.
    3. Is there a way for ABS to kick in under that circumstance or is this a product of the design
    4. Is it possible this was really fixed for $8?
     

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  2. Tombukt2

    Tombukt2 Senior Member

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    Vehicle:
    2009 Prius
    Model:
    Base
    And gearing all this UC regenerative breaking happening on the display when you're breaking taking foot off the gas the blue lines all of that yes or no?. Slamming on the brakes should activate ABS and if you're in the wet or semi ice conditions or any of that stuff the skid control is going to start the flash and all kinds of fun things are going to go on If you're in panic mode you may not see all those things happen because you're worried to death you're going into the drink or something possible accidents generally scare the shit out of people. I've put a bunch of these ABS actuators on generation 2s usually when you have the accumulator low pressure and the motor business running continually and all that sort of thing there's some kind of a leak somewhere if you don't see it on the ground it's internal just means we don't get to see it It's not squirting out onto the floor and the fluid's not vanishing. You can drive like that probably for years I'm not one to ever really have to panic break personally but I guess it could happen at any minute but I'm a pretty calm sort I'm not one to just slam on the brakes I'm able to steer around you and keep going well it was the sidewalk No big deal nobody's on it anyway.
     
  3. Kapcreations

    Kapcreations New Member

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    Location:
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    Vehicle:
    2006 Prius
    Model:
    N/A
    It's odd. After swapping out the relay, the lights have gone away. No more open circuit and no more low pressure warning. No lights flash when braking.

    I would've expected the ABS to kick in when slamming on the brakes at 50 mph, but that is not the case. It just locked up.
     
  4. Tombukt2

    Tombukt2 Senior Member

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    Location:
    Durham NC
    Vehicle:
    2009 Prius
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    Base
    Yes I would expect the ABS to activate on a panic braking situation four wheels are not supposed to lock up and you're not supposed to turn sideways so on and so forth like something in a Magnum PI episode so I would be looking into that You keep saying your pump is not running and the accumulator is not getting pumped up but if that was the case my friend I think you would have near no breaks in the rear and your pedal would feel like a 1969 Dodge truck without a brake booster and For drum brakes