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ABS Issues with 2003 Prius

Discussion in 'Generation 1 Prius Discussion' started by lordsquirrel, Sep 6, 2014.

  1. lordsquirrel

    lordsquirrel New Member

    Joined:
    Sep 6, 2014
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    Location:
    Asheville, NC
    Vehicle:
    2003 Prius
    Model:
    N/A
    Hopefully I don't step on any toes by asking this. I did use the search and couldn't find anything that explained what's going on with my car.

    Alright, so I originally bought a used '03 Prius a few months back, knowing that the car had brake issues. A test drive produced a battery problem (a 4.6V cell that has since been replaced). The dash lights would flicker while the car was under duress and the vehicle would not go higher than 35mph.

    I took the car to a normal mechanic and he produced a set of codes for me ( c1251, c1252, c1253, c1256, c1214, p3000).

    I was told by one of the guys at Taylor Automative (Sanford, NC), That there was a 90% chance the ABS issues would resolve themselves after replacing the battery.

    So I replaced the bad cell myself, put everything back where it belonged, and test drove it. The ABS light remained and the brake, while not as bad, was still undependable. A second test drive to see if the flickering would reoccur, showed that the issue had for the most part been solved. However on the last mile of the test drive, the gas engine went into overdrive and would not exit it (similar to how the car behaved on the first test drive, just with much less flickering of the dash). While in overdrive the car had issues maintaining a speed over 42mph.

    Can someone explain to me what I am missing? Or what ABS breaks have to do with what (somewhat clearly) seems to be an electrical/computer problem? Also does anyone have documentation for diagnosis of an ABS issue or a way to enter some sort of diagnostic mode for it?

    I've looked all over the place for documentation (including this forum) and the information was either lost to time or behind paywalls. Taking this car to a mechanic is not a realistic option for me.

    I appreciate any help you guys have to provide.

    Edit. Oh and the car is not beeping at me. Just a console warning 'car with exclamation mark' and the ABS light. Also the car, makes a light grinding noise when the wheel is turned to the right, anyone have any idea what that is?
     
    #1 lordsquirrel, Sep 6, 2014
    Last edited: Sep 6, 2014
  2. ChapmanF

    ChapmanF Senior Member

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    Location:
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    Vehicle:
    2010 Prius
    Model:
    IV


    Toyota has very complete documentation of everything you will need to know for diagnosis of your issue, how to get into the diagnostic modes, and how to interpret the results. It's just that you'll run into a small snag if you're expecting it to be free. It costs them time and money both to design and build cars and to write manuals, and they don't give either one away (though $15 for the documentation online at techinfo.toyota.com is pretty darned reasonable, and even the paper-manual pricing isn't excessive for what you get). You've already paid for the car, and if you're serious about wanting to be able to maintain it on your own, you know what the next step is.

    The manuals are divided this way: Volume 1 is diagnostic procedures and information for all the systems in the car. Volume 2 covers all the same systems with the actual mechanical procedures of getting to them for adjustment, replacement, or repair. The Electrical Wiring Diagram manual is about 200 pages telling you everything about how the car is wired, from circuit schematics to the physical routing of the harness and locations of connectors, to the shapes, pinouts, and part numbers of the connectors involved. There is also a pretty important manual called the New Car Features Manual, which concentrates on explaining what the different systems in the car are, what they're for, and how they are designed to work. The volume 1 and 2 diagnostic and repair information is all kind of built on top of that fundamental information. There's a New Car Features Manual at a new model's introduction, which was the 2001 model year for the Gen 1.

    Reading your post, I can see that you've made a lot of guesses about how your car works, and the guesses aren't all bad, but diagnosis always gets easier when you start with the most accurate ideas in your head about what's supposed to be going on, and the New Car Features Manual will help you a lot with that.

    Good luck,
    -Chap
     
    #2 ChapmanF, Sep 6, 2014
    Last edited: Sep 6, 2014
  3. lordsquirrel

    lordsquirrel New Member

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    Location:
    Asheville, NC
    Vehicle:
    2003 Prius
    Model:
    N/A
    After doing some more research and getting the car re-DST'd this morning, the issue is no longer documentation. It is that there is no reasonable way to DIY the brake boost assembly. So now I have a junk car sitting in my driveway. Thanks for the help anyways.
     
    #3 lordsquirrel, Sep 6, 2014
  4. ChapmanF

    ChapmanF Senior Member

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    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    PriusChat contributor rlin78 recently did exactly that just recently in a thread you could look up. You haven't got enough diagnostic information yet to be sure that's what yours needs though, so that could be time and money down a rathole if it isn't.

    I'd encourage you to list it for sale. What's junk to you might be a bargain to someone willing to diagnose the problem.

    -Chap
     
    #4 ChapmanF, Sep 6, 2014
  5. lordsquirrel

    lordsquirrel New Member

    Joined:
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    Location:
    Asheville, NC
    Vehicle:
    2003 Prius
    Model:
    N/A

    I looked into that thread and learned some interesting new ways I can handle the issue. So thanks for mentioning it.

    I do have someone looking out for potential buyers in the meantime though.
     
    #5 lordsquirrel, Sep 7, 2014
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