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Unknown Prius Problem

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Prius BMXER, Jan 4, 2009.

  1. Prius BMXER

    Prius BMXER New Member

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    Hello!
    I have a problem with my Prius that I cannot identify(nor can the mechanics). I took my car in to have it checked out when the red exclamation point problem light came on. A red square that said PS appeared in the left corner as well. They ran a diagnostic test and could not find the computer code for the problem.

    Whenever I turn the wheel all the way (in either direction) it will try and go in the other direction (making a popping sound). If the wheel is kept in that position the power steering shuts off completely (making parallel parking a bitch). I have to turn off the car and then restart it to get the steering to work again,

    Since the Prius (2004 model) does no have power steering fluid, I think it might be a transistor problem. PS could = power steering(?!?!)

    Pictures:
     
    #1 Prius BMXER, Jan 4, 2009
  2. Prius BMXER

    Prius BMXER New Member

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    I have to post 5 times to post pictures?
    Shucks!
     
    #2 Prius BMXER, Jan 4, 2009
  3. Patrick Wong

    Patrick Wong DIY Enthusiast

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    A few questions and comments:

    - What is the history of your vehicle - odometer reading, any front-end accidents?
    - Did you take your car to your Toyota dealer for service?

    Yes, PS appearing on the MFD means an electronic power steering problem. A DTC should have been logged.

    Assuming your Toyota dealer tech was unable to retrieve any DTC, please see the attached procedure that indicates the troubleshooting path to take. In brief the replacement of the power steering ECU is recommended if other checks prove negative. I suggest you inquire as to whether the tech followed the procedure; and if so what was the outcome.
     

    Attached Files:

    #3 Patrick Wong, Jan 4, 2009
  4. Prius BMXER

    Prius BMXER New Member

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    I'm at 126,000 miles. No front end accidents, just a few brushes with curbs.

    It was not at a Toyota. That was the next step we were going to take.

    I'll print out those PDFs and bring them in to the mechanic.

    Thank you.

    PS. How expensive is replacing the power steering ECU?
     
    #4 Prius BMXER, Jan 4, 2009
  5. Patrick Wong

    Patrick Wong DIY Enthusiast

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    I don't have info on that ECU but my guess is that it will be around $1K.

    In general, Prius DTC can be read reliably only with the proprietary Toyota diagnostic laptop or handheld tester - because many ECUs can generate DTC and this will confuse a generic OBD-II code reader. If the PS ECU logged a DTC, then it will be easier for the Toyota dealer tech to figure out the failed component.

    Good luck with your electronic power steering problem.
     
    #5 Patrick Wong, Jan 4, 2009
  6. maseace

    maseace Prius enthusiast

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    Parts.com has the PS ECU for $327. Don't let the dealer rip you off if you need it replaced.
     

    Attached Files:

    • PS.gif
      PS.gif
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    #6 maseace, Jan 5, 2009
  7. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Good find, that ECU is a relative bargain!
     
    #7 Patrick Wong, Jan 5, 2009
  8. CharlesJ

    CharlesJ Member

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    I cannot find the explanation in the owners book right now but I am pretty sure I read something about turning the wheel all the way to max, either direction, something about the power steering.

    Yep, found the brief reference to turning wheel fully to either direction 'for a long time.' This would cause damage to power steering motor.
    I guess then the question is- what is a long time.
    I found this in my 2008 manual at page 128. Chapter 2-1, driving procedures, under 'Avoiding Damage to Vehicle Parts'
     
    #8 CharlesJ, Jan 5, 2009
  9. snead_c

    snead_c Jam Ma's Car

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    It's never a good practice to turn a steering wheel "all the way" in either direction or in any car. With the short turning radius it should do fine with an almost all the way in the future. Good luck.
     
    #9 snead_c, Jan 5, 2009
  10. CharlesJ

    CharlesJ Member

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    Yes, I had cars that complained at such positions:D
     
    #10 CharlesJ, Jan 5, 2009
  11. donee

    donee New Member

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    Hi Prius BMXer,

    Did you have the steering recall repair issued for 2005 and earlier Prius performed? I think it covered 2004 , 2005 and some 2006 Prius cars.

    Could that mechanical issue be interpretted as an electronic problem by the electronics ? Maybe it allowed the steering to move the wheels such that it damaged an electric/electronic component of the system ?
     
    #11 donee, Jan 5, 2009
  12. richard schumacher

    richard schumacher shortbus driver

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    Hmm, I hope he hasn't been driving the Prius BMX-style :_>
     
    #12 richard schumacher, Jan 6, 2009
  13. Prius BMXER

    Prius BMXER New Member

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    Wow!
    I forgot about this thread! I tore my ACL and school just started so this whole ordeal has been put on the backburner.

    Incredible find on the ECU! Thank you! Much appreciated!

    The other night the wheel started turning by itself in the opposite direction I was trying to go. Not to mention the fact the steering just feels a tad off even when it isn't in the maxed turning position. The problem does happen when it isn't turned all the way as well.


    I don't think I've had any recall repairs. How do I go about doing that? Can I go into the dealer and ask them to check any possible recalls I qualify for?'
    Also, I'm new here obviously, but is there a way to fix the gas gauge's inaccuracy? I can put 4 gallons in and it says I'm at a full tank. I know the Prius operates on a fuel bladder or whatever and can't gauge the pressure right, but I'm wondering if they've remedied the problem?

    Thank you! I'm ordering that ECU!
     
    #13 Prius BMXER, Jan 15, 2009
  14. maseace

    maseace Prius enthusiast

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    For recall work, just call the closest Toyota dealer and give them your VIN, they will look up any recalls and schedule an appointment for you once the parts are available.
     
    #14 maseace, Jan 15, 2009
  15. richard schumacher

    richard schumacher shortbus driver

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    There's very little in the way of repairs or mods to be done about the fuel tank and gauge quirks. Pump slow, don't top off, try a different pump, try turning the nozzle upside down.
     
    #15 richard schumacher, Jan 16, 2009
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