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Brake, VSC, ABS lights all on, periodic strange action ONLY in reverse

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by gcarl, Jan 25, 2018.

  1. gcarl

    gcarl Junior Member

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    My 2004, purchased new in '04, here in St. Petersburg, FL, suddenly displayed all of these lights one morning last fall but my Smartgauge II (always connected) found no codes. Subsequently, I occasionally experienced a loud clunk noise and feeling as though the car had hit something (the reverse motion of the car stopped very abruptly!). After a few days of these experiences, I was able to get into my independent garage, hoping that they could better find some codes being thrown.
    After several hours, the shop owner called to say that they could find no error codes and that I might have to go to Toyota (NOT good news locally). I went to pick up the car and when I got there the shop owner advised that he had subsequently decided to try unplugging my Smartgauge, and the warning lights immediately went out.
    I subsequently left the Smartgauge disconnected and for several weeks experienced NO abrupt stopping/clunking or warning lights ...until now, when ALL of these peculiarities have returned. I have not reconnected the Smartgauge and have an appointment tomorrow with my independent shop. Any thoughts from Gen II owners? [email protected]
     
    #1 gcarl, Jan 25, 2018
  2. valde3

    valde3 Senior Member

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    First check your 12V battery and connections near it. It could cause random problems, theoretically clean codes, and a problem with parking pawl motor (causing the abrupt stop in reverse). Also maybe it could just a bad parking pawl motor.

    Have you ever gotten a problem with parking pawl motor warning on MFD? That normally comes with bad 12V battery or bad parking pawl motor.
     
    #2 valde3, Jan 25, 2018
    Last edited: Jan 25, 2018
    SFO likes this.
  3. gcarl

    gcarl Junior Member

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    Checked yellow top12V battery, no corrosion on/near, voltage at battery 12.7. disconnected positive cable for a couple of minutes to try to clear codes, if any. Reconnected, all error lights still on.
     
    #3 gcarl, Jan 25, 2018
  4. valde3

    valde3 Senior Member

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    Did you check the battery voltage after Prius has been OFF for at least an hour? If yes then that’s a good battery.

    If the error light’s come back on immediately after startup that means there should be codes. The codes are probably in braking system as those don’t clear with just unplugging the 12V battery. Maybe your or the shop code reader just couldn’t read them. Could the code reader talk to all modules? There’s a way to clean and read them with just peace of wire connected to DLC. But that just gets you a base codes.
     
    #4 valde3, Jan 26, 2018
  5. gcarl

    gcarl Junior Member

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    Car had been off overnight (more than 14 hours). Thanks for your suggestions!
     
    #5 gcarl, Jan 26, 2018
  6. ChapmanF

    ChapmanF Senior Member

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    As others suggest, fastest way to find out why your car lit those lights for you is to read the trouble codes. Everything else is just stuff to spend time on before getting around to reading the codes.

    -Chap
     
    #6 ChapmanF, Jan 26, 2018
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