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Brake Warning Light on Dash...

Discussion in 'Gen 2 Prius Main Forum' started by inframan, Sep 8, 2022.

  1. inframan

    inframan Junior Member

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    2009 Prius w/85k miles.
    Brake Warning Light (yellow one on dash, not red one on left) is constantly on now.
    Brake fluid level at max. Brakes feel Ok.
    Could that mean I need new brakes?
    Toyota manual doesn't say much (except take it to the dealer).

    TIA.
     
  2. Tombukt2

    Tombukt2 Senior Member

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    The yellow one on the dash is the ABS light?
     
  3. ChapmanF

    ChapmanF Senior Member

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    Whichever one of the brake -related lights it is, one finds out what it means by reading the trouble codes that caused it to be lit.

    If you don't have access to a code scanner that can do that (and not all code scanners will see a Prius's brake codes), the fastest and easiest way is to put a short piece of skinny wire between the Tc and CG terminals of the car's diagnostic connector, turn the car ON, and count the flashes of the dash lights.

    A quick search of this forum will find a bunch of older threads with pictures and more detail on how that's done.
     
    Longinus876 and PriusCamper like this.
  4. inframan

    inframan Junior Member

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    The one to the left of ABS. Looks like a circle with ! in center & calipers on sides. Matches the tire warning light which is also always on now even though my tires are fine. Hmmmm.
     
  5. inframan

    inframan Junior Member

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    I have a generic code reader but thought I'd ask a simple (I thought) question first. Am in the process of rebuilding a 7 yr-old self-built PC w/new mobo & cpu to run Win11. One set of problems at a time.
     
  6. dolj

    dolj Senior Member

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    A generic code reader will likely be inadequate. It likely can only read basic brake, engine, and (if you're lucky) TPMS codes.

    In any case, using the blink code method mentioned by ChapmanF will get enough information to go on with.
     
  7. PriusCamper

    PriusCamper Senior Member

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    Once you tell us the error codes and subcodes related to that dash light we can help you explain how urgent or not urgent the repair work is. Have you had the tires rotated or brake work done recently?
     
  8. ChapmanF

    ChapmanF Senior Member

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    No reason not to try the generic code reader. It will either show the brake codes or it won't.

    If it doesn't, the flash-counting method will still work. At least as long as you don't push the 'clear' button while trying the generic reader.
     
  9. PriusCamper

    PriusCamper Senior Member

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    If you're good at windows computers and have a Prius, consider buying a mini-VCI plug online that comes with Toyota Techstream software. It's challenging to get it setup but you'll then have the same software Toyota Dealerships have. In the meantime, stop by any auto parts store and ask them to read the error codes for you. It's a free service.
     
  10. ChapmanF

    ChapmanF Senior Member

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    OP has a generic scan tool (which may or may not show Prius brake codes), so that might be the easiest thing to try first.

    If that doesn't show the brake codes, any auto parts store is likely to also have a generic scan tool, which may or may not show Prius brake codes. So that would be another option, although it might just be faster and easier to keep the car where it is and use the flash-counting method.

    As terminology goes, the light that looks like ((!)) is called the ECB light (electronically controlled braking). It does look a lot like the tire pressure light, but if you look closely, you'll see the bottom of the tire pressure icon has treads. :)
     
  11. Tombukt2

    Tombukt2 Senior Member

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    I know the Innova brand of scanners will read the Prius ABS codes at least to the pull generics. My tech stream showed same . Twas all actuator or pump and resvoir right behind the inverter The left corner thereof anyway
     
  12. ChapmanF

    ChapmanF Senior Member

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    As there are around 200 different brake trouble codes meaning different things, I'll reserve judgment for now on what the problem might be.
     
  13. inframan

    inframan Junior Member

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    Not getting any codes on my code reader so I'll have to go by my local NAPA. Will report back when I find out anything.
    Now to find out how to activate TPM on my new mobo...
     
  14. ChapmanF

    ChapmanF Senior Member

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    Be prepared for the possibility that NAPA's reader won't show the codes either.

    In that case, you will still be able to get the codes using the jumper-wire method and counting light flashes.

    Just be sure not to let the NAPA guys say "well, we didn't see any codes, but we helpfully cleared them for you", because then you won't be able to get them yourself, until they come back.
     
  15. highmilesgarage

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    there are some parts store that has updated scanners than can read extra modules (ABS and Transmission codes) Oreilly and Autozone has the Innova scanner available (in my area) Innova is great but not really that comprehensive, I won't buy that overpriced obd2 scanner either. Advanced Auto still has an antique obd2 scanner that they plug into a printer to show the codes.

    Autel MaxiAP is a cheap alternative to Techstream (no laptop required) and is available in Amazon for less than $100. I use Xtool A30D now because of bi-directional features and no license fees (yearly) for all brands/models of cars (Autel will give you unlimited license for 1 and going to be $21 yearly for extra brand)
     
  16. Longinus876

    Longinus876 Junior Member

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    No, it's not. The ABS light is clearly labeled.
     
  17. ChapmanF

    ChapmanF Senior Member

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