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Prius won't go into ready mode after replacing 12v battery

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Scott M. Bleeker II, Aug 19, 2018.

  1. Scott M. Bleeker II

    Scott M. Bleeker II New Member

    Joined:
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    Fairfield NJ
    Vehicle:
    2005 Prius
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    N/A
    The other day I started my 2005 prius and after driving a few miles I got the red triangle and pulled over somewhere safe to try to diagnose the problem. Upon turning the car off and on again it failed to go into ready mode, so I checked the diagnostic mode and the voltage of the 12v was fluctuating within the low 11s and high 10s so I decided that it was pretty much dead. I replaced the battery but the same problem still persists and I can't get the car to go into ready with the new battery resting at about 12v-11.9v. The brake lights also work perfectly fine so I'm pretty clueless on how to proceed.
     
    #1 Scott M. Bleeker II, Aug 19, 2018
  2. JC91006

    JC91006 Senior Member

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    Did you mess with the orange interlock switch on the hv battery? If you did, just go back in there and lock it. Press/slide it downward towards the floor and you'll hear a click. That locks it
     
    #2 JC91006, Aug 19, 2018
  3. bisco

    bisco cookie crumbler

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    you need to charge up the 12v. although new, it has been sitting too long.
     
    #3 bisco, Aug 19, 2018
  4. hchu1

    hchu1 Active Member

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    Location:
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    Vehicle:
    2014 Prius v wagon
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    Two
    Check your grounds, they could be corroded or loose.
     
    #4 hchu1, Aug 19, 2018
  5. Scott M. Bleeker II

    Scott M. Bleeker II New Member

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    Location:
    Fairfield NJ
    Vehicle:
    2005 Prius
    Model:
    N/A
    I tightened the ground from the negative terminal which was a bit loose but I'm still having the same issue. The battery is currently reading from 11.7-11.9v depending on what is being powered. What voltage does the battery need to start normally? >12v? Also I never touched the orange disconnect and it seems to be properly in place. I don't currently have a battery tender so I'm going to go out and buy one now
     
    #5 Scott M. Bleeker II, Aug 20, 2018
    Last edited: Aug 20, 2018
  6. Scott M. Bleeker II

    Scott M. Bleeker II New Member

    Joined:
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    Location:
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    Vehicle:
    2005 Prius
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    N/A
    Scraping off the corrosion from all the connections seemed to do the trick! Thanks for all the help.
     
    #6 Scott M. Bleeker II, Aug 20, 2018
  7. RacerM

    RacerM Junior Member

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    Location:
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    Vehicle:
    2005 Prius
    Model:
    Four
    Just stopping by to say thank you. Attempting to diagnose the "Check Hybrid Battery" message and had left the lever unlatched.
     
    #7 RacerM, Oct 5, 2020
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