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Keeping our 12V battery properly charged?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by odub, Jul 23, 2022.

  1. odub

    odub Junior Member

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    Here's our situation: our 2005 Prius will go for days not being driven (it's our second car but during the pandemic, we transitioned to being a mostly 1-car couple) and all those days of inactivity eventually drain the battery dry.

    Our cars sit on an open driveway (our house didn't come with a garage) which makes things more troublesome to deal with.

    I've tried a solar-powered trickler but I'm guessing I didn't hook something up right because 12V was very very low this morning and then watched as it just flat out died.

    A plug-in maintainer/trickler would make more sense but without a garage, I'm not sure what's the best way to go about using it:

    1. Keep the hood slightly popped and use the maintainer on the battery connects on the front of the car? It's less direct but at least it'd be discreet and it wouldn't allow people to get into the car.

    2. Keep the trunk slightly popped and use the maintainer on the actual 12V battery? The problem here is that it allows people into the car.

    Any other suggestions of what might work here? Thanks.
     
    #1 odub, Jul 23, 2022
  2. TMR-JWAP

    TMR-JWAP Senior Member

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    Any small trickle charger/maintainer will have a power cord thin enough to allow closing the hood or the trunk hatch. Quite often, I've left a trickle charger/maintainer connected to the 12v battery in the trunk and just closed the hatch and locked the car if I don't plan to use the car for a while.

    12v battery life can be greatly extended by disabling the SKS system using the "key" button located below the steering wheel. You'll have to use the lock/unlock buttons on the FOB while its disabled, and will have to insert the FOB into the dash slot to start the car. You can go back to normal SKS use at any time by putting the button back to its normal position.
     
    #2 TMR-JWAP, Jul 23, 2022
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  3. SFO

    SFO Senior Member

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    You can use the jump point under the hood, or crack one of the windows enough to feed an extension cord through, then lock the vehicle.

    If parking in direct sun, with no expected weather, why not crack all 4 of the windows a few inches and save your HV battery from heat soak.

    Curious how many times the catalytic has been stolen.
     
    #3 SFO, Jul 23, 2022
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  4. bisco

    bisco cookie crumbler

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    in your situation, i would simply put a maintainer under the hood when parked, drop the cord through the engine bay onto the ground, and plug in an extension cord.
    removal when you're going to use the car would take a minute.

    this is what i do with my rarely used pickup and it's oem 17 year old 12v.
     
    #4 bisco, Jul 23, 2022
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  5. odub

    odub Junior Member

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    So far? NONE. It certainly happens in our area but I think because the car is parked on a driveway, next to the house (and next to motion-sensitive flood lights), that tends to deter folks. Fingers crossed
     
    #5 odub, Jul 23, 2022
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  6. Tombukt2

    Tombukt2 Senior Member

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    As long as you're not in California this is a mild inexpensive inconvenience you can even mark the car some kind of way or paint the thing down there so it looks like it's been fooled with and people will move on generally that sort of thing does work. But it sounds like you're 12 volt maybe on the way out
     
    #6 Tombukt2, Jul 23, 2022
  7. Another

    Another Senior Member

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    Just curious. Which solar charger did you try?
    This one by Battery Tender works for many people and uses the OBD2 port for easy connection. No need to mess with battery connections.
    There is an extension wire also to reach all the way back to rear window if that’s desired.
     
    #7 Another, Jul 24, 2022
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