ABS pump replacement and brake light, ABS light, VSC light on and limited brakes?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by James2005, Dec 11, 2023.

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  1. James2005

    James2005 Junior Member

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    A year or so ago I replaced my ABS pump with an ebay module allegedly from a low mile Prius. Ever since then the ABS, VSC, and brake system warning light (exclamation point and circle) have been on continuously. Recently, when driving through heavy rain or through standing water the emergency brake light also comes on and I lose front brakes. I have to use the paperclip method to reset the brakes and that seems to work. Anyone know why all the lights would stay on after replacing the ABS pump or why water would cause the brake light to come on?

    Vehicle details: 2005 Prius, 330K+ miles (Odometer stopped at 299,999 but trip odometers still work)
     
    #1 James2005, Dec 11, 2023
  2. ChapmanF

    ChapmanF Senior Member

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    #2 ChapmanF, Dec 11, 2023
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  3. James2005

    James2005 Junior Member

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    #3 James2005, Dec 12, 2023
  4. James2005

    James2005 Junior Member

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    From what could tell searching online, these are the descriptions of these codes.

    32 - Front Speed Sensor LH Circuit
    36 - Foreign Object is Attached on Top of Front Speed Sensor LH
    43 - Acceleration Sensor Stuck Malfunction
     
    #4 James2005, Dec 12, 2023
  5. ChapmanF

    ChapmanF Senior Member

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    Partial credit. :) You have to keep track of which code blinked on which light, as the meanings are different. Several common ones are explained right on this page:

    https://priuschat.com/wiki/blink-a-k-a-flash-codes-how-to/

    where you can find that 43 on the VSC light just means "go look at the codes on the ABS light", and likewise 36 on the ECB light just means "go look at the codes on the ABS light".

    The 32 on the ABS light is indeed trouble code C0205, whose fortune cookie is "front speed sensor LH circuit". There are seven pages of troubleshooting ideas for that code in the repair manual.

    Toyota Service Information and Where To Find It
     
    #5 ChapmanF, Dec 12, 2023
  6. James2005

    James2005 Junior Member

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    Thank you, in my first response I did post the codes by warning light.

    Codes:

    Brake System Warning Light - 36
    ABS - 32
    VSC - 43

    Any reason why driving through standing water (normal after a heavy rain) would cause the emergency brake light to illuminate and the car would lose front brakes? That has happened 3 different times over the last 6 months.
     
    #6 James2005, Dec 12, 2023
  7. ChapmanF

    ChapmanF Senior Member

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    I suppose I must have noticed that your post #3 had them by warning light, as otherwise I would not have been able to give you the correct meanings for all three of them in post #5.

    In the standing-water question, by "emergency brake light" do you mean the red word BRAKE ?

    It might be helpful to give more detail about what happens when you say you "lose front brakes".

    Actual loss of the front brakes is awfully difficult to make happen ... even in the fail-safe mode, the front brakes are the ones you don't lose.
     
    #7 ChapmanF, Dec 12, 2023
  8. James2005

    James2005 Junior Member

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    yes, the red word BRAKE light (the emergency brake light) and there is a significant loss in braking, as if the car went from power to non-power brakes. Force applied to the brake pedal is significantly increased and stopping distance is also increased. I thought I read on these forums that people who experienced similar condition was due to a loss of front brakes, but I could be wrong.
     
    #8 James2005, Dec 13, 2023
  9. ChapmanF

    ChapmanF Senior Member

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    Any other warning lights when that happens?

    The behavior seems a lot like fail-safe mode, but the absence of any other lights would surprise me.
     
    #9 ChapmanF, Dec 13, 2023
  10. James2005

    James2005 Junior Member

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    No additional warning lights or noise when this happens.

    I have used the paper clip in the 4th and 13th slot of the OBD then turn the car on (foot off brake) and pump the brake pedal 8 times in 5 seconds and that “resets” the brakes and the red BRAKE light goes out and brakes return to normal operation.

    However, the BSW (Brake System Warning Light), ABS and VSC are always on (ever since I replaced the ABS pump).
     
    #10 James2005, Dec 13, 2023
  11. ChapmanF

    ChapmanF Senior Member

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    Have you used the CG to Tc jumper, without the pedal pumping, to obtain the trouble codes in the condition when all four lights are on? Any difference in the set of codes reported?
     
    #11 ChapmanF, Dec 13, 2023
  12. James2005

    James2005 Junior Member

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    I haven’t tried that, but I certainly can next time the issue arises.

    In the meantime, I am going to pull the front left whee and check the speed sensor and see what condition it is in.
     
    #12 James2005, Dec 13, 2023
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