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How long can i leave the car without disconnecting battery?

Discussion in 'Gen 3 Prius Main Forum' started by Dominic, Aug 18, 2010.

  1. Dominic

    Dominic New Member

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    I was just wondering... I am in the navy so i'm called to go away quite often sometimes for extended periods.

    I have read that the 12V battery will discharge itself if it the car is not being used frequently because it has the memory for everything (radio channels, time, trip meters, etc)

    my question is how long is it safe for me to just leave the car parked in my driveway without disconnecting anything and when should i disconnect it?

    (ie. if i go for 2 weeks, is it ok? what about 1 month? 2? etc. i'm just trying to figure it out and don't really want to learn the hard way!)

    thx
     
  2. bisco

    bisco cookie crumbler

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    we go to florida every winter and leave our 08 in the unheated garage for 6 weeks, no problem so far.:)
     
  3. andyprius

    andyprius Senior Member

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    This is such a difficult question because: each Prius is different. #2 poster is lucky. I think it has been said before that the parasitic drain is about 15ma. Then there is shelf life, probably in your case you should hook up a float charger which puts out about 1 ampere. Connect it so you can plug in the float charger easily and quickly. As I understand it the float charger does not charge but only maintains the voltage level, the battery will stay at a determined safe level.If that is not possible, to be safe I would disconnect the ground wire. Third option is to experiment. This is all assuming no extras are connected to the accessory plug in, audio equip. etc. :cheer2:
     
  4. Colonel Ronson

    Colonel Ronson New Member

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    its hard to say. it depends on ambient temperature. in my old infiniti, i left it parked in the garage for 6 months while i was away for my first year of college, came back, and it still started. Since the car is new, i think you'll be fine but safe bet is just to hook up a battery tender. If you disconnect the battery, it will eventually reset the ECU and you'll have to reprogram a bunch of stuff.
     
  5. seb33

    seb33 Junior Member

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    I'm leaving tomorrow for a vacation overseas for 2 1/2 weeks. It should be okay, right? I was going to park it in a friends driveway, but if its a concern I could leave it at home and have my sister drive it after a week or so to recharge. She's a little afraid to drive it, so it would be best if I didn't have to worry about it.
     
  6. andyprius

    andyprius Senior Member

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    Normally it is nothing to worry about, but Dominic said he was in the Canadian Navy so he could be gone an indeterminate length of time. The important point is to lock the car when you leave, as any door left ajar or a dome light will drain the battery. The process of locking the car insures that nothing is left on. Have a good vacation!:)
     
  7. dandeman

    dandeman Junior Member

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    If it is left in your driveway, would presume that means AC power is close by..

    I would get one of the chargers linked to below and leave it connected to the 12volt battery when you are gone. I have a number of these for tractors, a engine powered welder, even my Toyota 4Runner that I use to keep the batteries in good condition.

    BatteryMINDer® Plus 12 Volt 1.33 Amp Charger-Maintainer-Conditioner (Desulfator) | All | Battery Chargers by BatteryMINDers.com

    These are pulse chargers and are excellent in preventing/breaking up sulfation.. There are a lot of positive attributes stated in the literature, but this is one case where they are true.

    I'm familiar with pulse charger technology from commercial DC Plants we design and install. Pulse chargers in general are a more expensive technology, but better way to keep batteries in good condition.

    These also come with a fused connector you can permanently connect to the battery and have a pigtail through the grill (or handy in the trunk) to connect the charger to..
     
  8. jayman

    jayman Senior Member

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    If at all possible, hook up the Battery Minder. With my '04 Prus, and now my '07 FJ, they sat around enough that dead batteries were a worry

    Hook up the Battery Minder harness directly to the battery, plug it in, and cease worrying about it. The Battery Minder also prevents sulfation so the battery will last much longer
     
  9. BBaggins

    BBaggins New Member

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    Left my 2010 III in a unheated garage for over four months last winter. No battery minder or anything and it started just fine when the snow melted outside. The traction battery was still up!
     
  10. Roland1555

    Roland1555 Senior Member

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    I have to admit that I'd read of other owner's having to boost or jump start theirs cars after a short period, so I purchased one of the portable battery jump boxes just in case mine was going to need a jump this last winter.


    It never did, but I always leave the car outside all year and had knee surgury in January, so my car was not used for almost two weeks.

    Granted, west coast winters are easier than most, but I was happy to find that the car powered up just fine as it does every morning once I was able to return to driving it.

    My commute to work is about 40 minutes each way, mostly highway and I believe it helps as the Prius charges the small 12 volt battery differently than conventional cars with alternators. If you only do very short trips, it might be the case that your battery never is fully charged and with the small parasitic drains that all modern vehicles suffer to some degree might require a jump box should you be leaving the car unused for a month or two.

    Roland.
     
  11. fed123

    fed123 Member

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    Was away in Europe for two weeks. Came back Aug 7th and Gen III fired right up.