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Anyone Using A Battery Tender On A Prius?

Discussion in 'Gen 2 Prius Technical Discussion' started by Walker1, Apr 1, 2008.

  1. Walker1

    Walker1 Empire

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    I have a 2006 Prius & am buying an '08 in about 2 weeks. My 2nd car is a Honda that I have a battery tender on as it sits 95% of the time. When we get the '08 Prius the '06 will sit more as it has almost 30,000 miles on it.

    I read a 2005 post on battery tenders & does anyone who has a Prius use one? If so, can I hook up the leads under the hood or do I have to connect them to the 12 volt battery in the hatch? Thanks.
     
  2. jayman

    jayman Senior Member

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    I have a 2004 and although it is used almost daily, I had trouble the first winter. The combination of -40, Max Heat, constant electric defrost, headlights, etc, all managed to put the 12 vdc battery into a discharged state

    I managed to pick up some VDC Battery Minders at an auction. I wired directly to the battery in the rear. Four years now, no issues

    I've attached a pdf of how it looks hooked up. I have a corrogated plastic wire sleeve covering the harness, which I removed to take the photo

    Hope this helps
     
  3. David Beale

    David Beale Senior Member

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    Yes, you can connect the battery tender under the hood. That's how I do it. I just use the clips that came with the battery tender, as I don't use it very often, though it is mounted on the garage wall beside the Prius.
     
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  4. Walker1

    Walker1 Empire

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    I don't mean to sound dumb, but where exactly under the hood are the 2 terminals? I have never had to look for them. Thanks.

    BTW, I have been using a battery tender on my Honda that only puts out 3/4 of an amp until it fills the battery. It's a Harley BT & I have 3 of them.;)
     
  5. Walker1

    Walker1 Empire

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    How many amps does yours put out?
     
  6. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Find the relay/fuse box near the inverter. Open the lid by pressing hard on the latch at the leading edge of the box, then lift the lid up. It will detach from the hinges at the back of the box so you can remove the lid.

    You will see a red plastic hinged cover in the upper left corner of the relay/fuse box. Open the cover. Now you will see the positive jump-start terminal.

    Attach the positive cable from your charger there. Attach the negative cable to unpainted metal on the body. Then you can turn on the charger.
     
  7. Walker1

    Walker1 Empire

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    Disregard my question on the location of the terminals under the hood. My wife & the Prius came home, so I looked it up in the manual. They say any unpainted nut/bolt under the hood is OK for the (-) clamp & I see 1 just above the fuse block location.

    So much for that. I have 3 tenders- 1 is for the garden tractor, the 2nd is on the Harley, and the 3rd is on the Honda. I swear by them as far as batteries lasting much longer than normal here in FL. Usually, you get about 2 yrs. usage out of a battery down here. I thought cold climates were harder on batteries, but it's not the case here.:p
     
  8. jayman

    jayman Senior Member

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    The older model Battery Minder put out 1 amp max. The new one puts out 1.33 amp max

     12 Volt-1 Amp  Charger and Maintainer

    Since the older model and the new one sense battery voltage/condition, they may be hooked up 24/7. If you have a trickle charger, do *not* use it. You will damage the battery

    The Battery Minder - I suspect other conditioner chargers as well - can *not* be used to recharge a dead battery. The instructions clearly state a conventional battery charger must be used to bring the battery up to 12 vdc.

    If the battery voltage is lower than 11, the Battery Minder is designed to not turn on at all
     
  9. Walker1

    Walker1 Empire

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    Got it. Thanks.
     
  10. Walker1

    Walker1 Empire

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    I bought all 3 tenders from the Harley dlr. as I don't ride the bike often enough to keep the battery charged. Some years ago motorcycle manufactuers decided to do away with the manual kick starter, so when your battery goes down you aren't riding.

    I had to call for a flat bed wrecker to tow the HD in to the dlr. That's when they told me about battery tenders. I've been using them for about 4 yrs. now & haven't lost a battery yet!:)
     
  11. jayman

    jayman Senior Member

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    If your tender is the Harley Davidson SuperSmart Battery Tender, then it appears to be a VDC without the desulfation function. They're safe to be left plugged in 24x7 and will keep the battery at the proper charge

    The VDC Battery Minder has the benefit of desulfating the battery as well. This will improve performance and life
     
  12. Walker1

    Walker1 Empire

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    Yes, The HD tenders are SuperSmart units. Good point.
     
  13. drhardee

    drhardee New Member

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    I've purchased a Sears Diehard Charger/Maintainer that includes a cigarette lighter interface plug (12v accessory plug) in addition to the battery post clamps. Is this a smart way to quickly connect/disconnect this float charger?

    This won't cause any sort of damage to the accessory systems, would it?
     
  14. Patrick Wong

    Patrick Wong DIY Enthusiast

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    The 12V power outlets are not connected when the car is IG-OFF, so using those outlets to connect your charger won't be helpful.
     
  15. krg03

    krg03 Not expert, just experienced

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    I use mine this way since I couldn't find a good way to mount the receiver plug somewhere at the front of the car (without making holes). I did the mod first that allows the accec. plug to be always on (one wire, 2 clips. don't buy it)
    coastaletech.com power_outlet_mod.htm
     
  16. cameljok

    cameljok New Member

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    Thanks for all of the info guys. I have a couple Deltran battery tender juniors and was told that it was killing the battery's on my three bikes. The bike batteries are X2 gel batteries and the guy at Batteries Plus said that the Deltran chargers so not charge gel batteries properly.

    I bought a Optimate 3+ and was told this is a smart charger. I installed the terminals under the hood and plugged in the charger. Hopefully there won't be any issues.
     
  17. M8s

    M8s Retired and Lovin' It

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    I have a Deltran "Optimate" 3 and a 3+ and use them when we leave our 2 Prii for weeks at a time. Works fine and no issues.
     
  18. dony71

    dony71 Junior Member

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    Do you know what size is this power outlet wire and green wire in the fuse panel? I plan to make jumper wire by myself by using quick splice connector
     
  19. ccdisce

    ccdisce Active Member

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    The DLC/OBDII connector has unswitched power, found this info in 1997 Tbird EVTM when I designed the Info Panel a few years back. There is a company in CA that sells receptacles and pins if you do not want to splice into the wires.
     
  20. dlandersson

    dlandersson New Member

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    Thx, exactly the info I was looking for