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Leaving 12V battery disconnected for a couple of weeks; any issues?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by srivenkat, Apr 23, 2013.

  1. srivenkat

    srivenkat Active Member

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    I will be out of town and so thought I would do this to conserve the battery. Any problems with doing this? I understand certain counters and such will be reset.
     
  2. kithmo

    kithmo Couch Potato

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    IIRC, electric windows auto function has to be recalibrated and you lose Nav memories and trip settings.
     
  3. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    You might consider hooking up an intelligent charger, the kind that can be left on indefinitely: they run through a charge cycle, then back off to intermittent, trickle charge.
     
  4. srivenkat

    srivenkat Active Member

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    Thanks for all the info/replies.

    I have been wanting to sort of "reboot" the system for a while now and this seems to me like a good opportunity to do that. Any difference in leaving it disconnected for a few minutes (as in a typical reboot) vs. a few weeks?
     
  5. tumbleweed

    tumbleweed Senior Member

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    I have had my 12V battery unhooked for maintenance and the only thing I remember losing is the audio system presets, all the Nav stuff and blue tooth seem to be NV RAM. I don't remember for sure about the trip mileage but I think it was OK too. Let us know after you try it.
     
  6. rrg

    rrg Active Member

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    Fold down the back split seats if you remove the 12v battery connection.
    The hatch will not open from outside to get back in and re-attach the connection.
    I forgot once and it's a pain to jump over the seats. I removed all the trunk trays to gain easy access upon my return.
    my2cents
     
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  7. srivenkat

    srivenkat Active Member

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    Thanks for mentioning this. Alternatively, I might be able to connect the jumper cables in jumpstart configuration to the jump points under the hood from my other car (a Camry Hybrid) and then be able to unlock the hatch?
     
  8. Mike500

    Mike500 Senior Member

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    Two weeks? No need to disconnect the battery. It will start up just fine.
     
  9. hlunde

    hlunde Member

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    Alternatively, if you're in a secure location like your own garage, just leave the hatch unlatched, placing something like a folded blanket in the latch area to avoid unintentional re-latching.
     
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  10. Mauiman

    Mauiman Junior Member

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    If I leave the car unlocked when disconnecting the 12V battery during my extended absence, will I be able to open the hatch in back after my return since it wasn't locked to begin with? I've had to crawl over the seats in the past and what a pain.
     
  11. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    The hatch latch is electric, so no.

    As long as the 12 volt is disconnected, I would just lay a heavy glove over the latch mechanism on the threshold. Stuff the disconnected negative lead into the other glove, for safe keeping.

    There is another trick, you shift the latch mechanism with a screw driver tip, so that it's prelatched. I think it works out about the same, and the glove method is so simple.
     
    #11 Mendel Leisk, Jul 3, 2019
    Last edited: Jul 3, 2019
  12. CR94

    CR94 Senior Member

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    Pushing the latch into closed position by hand while the hatch is open is not difficult. That's less conspicuous than the "glove method," and does not require keeping track of an extra piece of clutter in the car. I do it frequently, for other reasons.
     
  13. Grit

    Grit Senior Member

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    Ah, the crawl of shame. Been there, dusted that.