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12v Question / Infrequent Driving

Discussion in 'Prime Main Forum (2017-2022)' started by cnm11201, Jun 20, 2020.

  1. cnm11201

    cnm11201 New Member

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    I'm very close to buying an XLE because the incentives are so great in NYC. I often go 5-7 days without driving my car, and some weeks I'll only drive it for 40 minutes. Also, living in NYC, I'll have few to no opportunities to give it a full charge. Am I going to wind up with a dead 12v battery on a regular basis?

    Thanks!

    Claude
     
  2. Rob43

    Rob43 Senior Member

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    Assuming your 12v battery is in good shape when you purchase, you should be good to go based on your 5 to 7 day schedule. This problem really shows itself when someone is dealing with a mediocre condition 12v battery that's then left sitting for longer than you stated.

    12v Battery Is Discharging, Re-Charge Now ! | PriusChat


    Rob43
     
  3. Tips

    Tips Member

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    I don't believe you will have issues. We just left our 2020 for 7 days it did not hesitate too start. I believe this battery is the power supplier for the PC ,so it is important! Talk to the parts department and find out if the 12 volt is covered by warranty! There has been discussions about this. Some say it is not covered by warranty, I believe it is, so I would check this out!
    Have you tried out the new Prime? If you haven't you are going too be impressed as it is a beauty! It is nice too drive in ev or hv, so try one out and join the group!

    Posted via the PriusChat mobile app.
     
  4. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    Can you clarify? I'm guessing you're street parking, no access to 120 volts for a charger?
     
  5. Salamander_King

    Salamander_King Senior Member

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    As said above, if the 12v battery is new and healthy, once in week drive for ~1 hour will be OK. Of course, that depends on how you use and take care of your car. Having accessories like a 24/7 dashcam or alarm system may drain the 12v quicker. Leaving the car on ACC for a long time will do the same. I have been checking my 2020 PRIME (4 months old) that is now being driven only once a week ~1hour, but the 12v have been holding above 12.3v without charging.

    That being said, if you continue to use the car that way for a long time, over months and years, the 12v battery will gradually decrease the resting charge. I would think regularly charging 12v battery (once every few months would be sufficient) would bring this resting SoC to normal high. You said you can't charge your 12v battery. Are you not going to charge your traction battery? If you have access to a 110v outlet, then charging the 12v battery is as easy as charging the traction battery, after you invest $20-$200 on a smart charger/maintainer.
     
  6. ETC(SS)

    ETC(SS) The OTHER One Percenter.....

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    Probably not.
    New Car.
    New 12v battery.

    If these things can't be parked for a week without calling a tow truck then you have a warranty beef, and perhaps need to reconsider your car shopping habits.

    The incentives for the Prime in NY means that you can probably get one for about the price of a “wireless” or non-Prime Prius.
    If you have access to a 120v outlet THAT YOU HAVE PERMISSION TO USE then you always have access to a full traction battery.

    With access to an outlet you can also spend $20 on a “Battery Tender” clone and never have to worry about a dead Aux (12v) battery even if you have to park your car for TWO weeks.

    Good Luck!

    PICTURES!!!
    (Or....it never happened.)
     
  7. FuelMiser

    FuelMiser Senior Member

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    Keep in mind: the 12V is only charging when the car is in READY i.e., when you are driving the car. It does not charge when have the car OFF and charging the big battery from a cable. Thus, if you're only driving a few days a week and for only a short time, the 12V will be in danger of running down. Do you have 120v available where you park the car to connect a trickle charger to the 12V?
     
  8. Trollbait

    Trollbait It's a D&D thing

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    Assuming you had one, was there issues with the 12volt in your previous car under the same conditions?
    The Prime charges up 12volt battery just like any other car, when the car is on. It does so even when the car is only driven in EV mode. So no problem with other cars, should be no problem with the Prime.
     
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  9. bisco

    bisco cookie crumbler

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    based on the link in post #2, i would either abstain, or buy a jump pack, and plan on more 12v purchases than normal.
     
  10. cnm11201

    cnm11201 New Member

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    Correct -- street parking with no access to a 120v except when out of the city

    Thanks for your thoughts! My main reason for checking out the prime vs the non-prime prius is it's several thousand dollars cheaper. I'm looking at $9100 in federal + state + manufacturer incentives, which more than makes up for the extra cost. Can I have a battery tender plugged in / installed all the time?

    I've had no issues with the 12volt in my current car, an '05 Toyota Matrix, but it's a dumb car....
     
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  11. Trollbait

    Trollbait It's a D&D thing

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    Yes, the battery tender can be plugged in all the time. They are slow rate chargers. When the battery is at 100%, they just provide enough energy to overcome self discharging. Just need an outlet for it.

    i believe the only major drain the Prime will have over the Matrix is the smart key system. There is a way of turning it off, but it isn't a simple switch like it was on my 2005 Prius. I have left that car sit, with the SKS on, for 5 days without problems starting up.

    Keep in mind the 12volt in a hybrid doesn't need the power to crank the engine. It just boots up the computer, and flips the relay to connect the traction battery.

    There are more reports of dead batteries here these days, but in most cases, the cars have been parked for far longer than 5 days, and are usually being driven for shorter periods than you report will be doing.

    If your use cycle does result in the battery being unable to start the car, it would happen with the nonplug Prius and most new cars.
     
  12. eatriceyo

    eatriceyo Member

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    i've been using a duracell battery charger/maintainer since this whole covid thing started and have nothing but great results. i leave it plugged in all the time and it even repairs and fixes slightly discharged batteries.
     
  13. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    Solar powered 12 volt charger? Just a thought, not sure how effective they are.
     
  14. Rob43

    Rob43 Senior Member

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    I run one on my Prime...


    Rob43
     
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  15. cnm11201

    cnm11201 New Member

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    Thanks everybody for allaying my concerns! Is a battery minder something I can ask the dealer to install at pickup?

    That was my next question -- thank you for answering it for me in advance :)
     
  16. Mendel Leisk

    Mendel Leisk EGR Fanatic

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  17. ETC(SS)

    ETC(SS) The OTHER One Percenter.....

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    Street parking.....
    Access to 120v - no.
    Battery Tender - no.
    Solar battery maintainer - ABSOLUTELY yes!

    Get somebody smarter than me.....(there are many to chose from) to recommend a model that works with the Primes.
    @Rob43 is a good gezample and he actually has a prime and knows that I equals E over R (in a classroom.)

    Two things to be mindful of:
    1. Using a solar cell to keep a 12v battery used to be as simple as jamming a solar cell into a cigarette lighter socket, but now you probably have to do a little more than that, and it's going to be model specific.

    2. Even in NY in the winter.....you can't turn off the sun.
    It's a safety feature. Otherwise? We humans would screw it up.
    This means that you're going to have to use a solar panel with a charge controller or battery management feature.
    However (comma!!!! pause for effect....) not all charge controllers are the same, because not all batteries are the same.
    BUT there are many choices out there for autos and they're as inexpensive as $20.
    The phrase that pays is battery maintainer.

    Good Luck!
     
  18. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    No I wouldn't think so. A straight forward on-board charger, one that plugs into 120 volt, yeah maybe. But whatever your doing, they will really soak you, and you may or may not be happy with the outcome. I would research and DIY if possible.
     
  19. Salamander_King

    Salamander_King Senior Member

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    Whatever you do, don't let a dealer do the battery minder installation even if they offer. They will charge you arms and legs for something so simple to use. That is for regular 12v battery charger not a solar set-up others are commenting above. A regular 12v battery minder is a small battery charger that connect directly to the battery posts in one end via alligator clips and plugs into 110v outlet either on the wall or to an extension cord. If you have no access to 110v outlet, it won't do any good to have a batterytender/minder/charger on hand. I bought NOCO Genius 2D onboard charger/maintainer to install it onboard under the hood of my PRIME. Most other chargers are portable and you do not have to install it under the hood. But you DO NEED 110v outlet accessible for this to charge the 12v battery.

     
    #19 Salamander_King, Jun 22, 2020
    Last edited: Jun 22, 2020
  20. cnm11201

    cnm11201 New Member

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    FWIW, I'm exceptionally unhandy, and wouldn't trust myself to do something like this myself.