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12v battery was disonnected, parking malfunction

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Jaydoc, Dec 6, 2015.

  1. Jaydoc

    Jaydoc Junior Member

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    Hi all

    I had the 12v battery of my Prius 2010 disconnected to install a backup camera, but then had a change of plans, so after a couple of hours I reconnected it. But when I started the car I got a yellow triangle exclamation and this error message -"p lock malfunction when parking , park in a flat place and apply parking brake securely".

    The car starts, shifts into reverse and drive, and does not roll on a flat surface when turned off.

    How can I fix this?

    Thanks.
     
  2. xliderider

    xliderider Senior Member

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    Ignore the error. If you don't get any more errors with subsequent starts, don't worry about it.
     
  3. Jaydoc

    Jaydoc Junior Member

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    Thanks @xliderider . I have taken the car for a drive, parked it on some pretty steep slopes, but the parking light on the center console does not work, and the park indicator does not get highlighted. But when I turn off the car, it does not roll.

    I also installed a new head unit. There was a bolt that slipped and fell into the central console housing. I tried reaching it and gave up. I am unsure if I accidentally disconnected some wiring underneath it.

    The error is persistent and comes on with each restart.
     
  4. JC91006

    JC91006 Senior Member

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    what's your battery health/voltage?
     
  5. bisco

    bisco cookie crumbler

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    the p lock malfunction is a warning and usually nothing to do with the parking lock. if the battery is good, recheck your wiring.
     
  6. Jaydoc

    Jaydoc Junior Member

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    1. My battery outputs 10.6v when the car is on but no accessories are on.

    2. Which wiring? I have a few wires that need to be tucked away from the head unit I installed. Would that be a problem?

    Thanks.
     
  7. JC91006

    JC91006 Senior Member

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    time to change the 12v battery
     
  8. bisco

    bisco cookie crumbler

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    ,battery connection wires. but if you're reading 10.6 at the battery posts with a meter, it's toast. you could try charging it, how old is it?
     
  9. Jaydoc

    Jaydoc Junior Member

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    I don't think it's been replaced, but I am not sure. In any case, I never had this problem today before I disconnected and then reconnected the battery negative terminal? I never had this problem before today. There was some sparking when I put the bolt back on the terminal post. Could that be the issue? If so I will take it to a mechanic to replace the battery.
     
  10. bisco

    bisco cookie crumbler

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    i doubt it. did you test it at the terminals?

    wait, you can install a head unit, back up camera, but not a 12v battery?
     
  11. JC91006

    JC91006 Senior Member

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    The issue is the battery is at least 5 years old and is reading only 10.6 volts. A new battery should read around 12.9 volts
     
  12. Jaydoc

    Jaydoc Junior Member

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    @bisco

    I haven't installed the camera yet. Will do so in a week. And yes, I can follow instructions pretty well when doing something. If I find some clear instructions on how to change out the battery I will try it out myself.

    @JC91006

    I will try the battery change and will let you know.
     
  13. bisco

    bisco cookie crumbler

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    there are threads here with pics, it's not hard at all. all the best.(y)
     
  14. mrbigh

    mrbigh Prius Absolutum Dominium

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    you have a 2010 with the original Aux battery??????????????????
    It is time to replace it, it doesn't last with a good state of health more than 5 years............
    My choice was the correct Optima Yellow top.