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Replacing 12V Battery in 2009 w/o SmartKey

Discussion in 'Gen 2 Prius Main Forum' started by skopstein, Sep 23, 2012.

  1. skopstein

    skopstein Junior Member

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    I have a 2009 w/50K miles and my 12V battery needs replacing. My car does not have the SmartKey system, and I'm having trouble finding a replacement battery. Has anyone been successful with this?

    I purchased the Optima DS46B24R, but it is quite a bit longer and a bit higher than the OEM battery S34B20R. I was told by Optima that the battery would fit a car with or w/o the SmartKey and the battery pad was the same. But it looks to me like the hold-down bracket would have to be modified or replaced to make his work. I could cut off the one side of the bracket that keeps the battery from sliding forward, which I think would allow it to fit. But the additional height of the Optima prevents the top bracket from seating properly.

    Has anyone been successful with this, or am I stuck with the Toyota battery?
     
  2. Britprius

    Britprius Senior Member

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    You can purchase the hold down bracket from Toyota for the larger battery. Some people on PC have just cut off the bottom of the bracket as you suggest without problems.
     
  3. usnavystgc

    usnavystgc Die Hard DIYer and Ebike enthusiast.

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    I can't believe you need a new battery after only 3 yrs. of use. Did you leave the dome light on every day???
     
  4. Britprius

    Britprius Senior Member

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    The non smart key battery has a hard life as it is even smaller than the smart key version (amp/hr capacity) this means if you sit listening to the radio or leave a light on it goes into deep discharge sooner. Also a 10amp/hr loss due to age on a 40amp/hr battery is 25% loss on a 30amp/hr battery it's a 33% loss so things snowball.
     
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  5. usnavystgc

    usnavystgc Die Hard DIYer and Ebike enthusiast.

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    Wow, that helps me understand it better. I would definitely upgrade the battery. Replacing a battery isn't that hard but doing it every 3 years is not on my list of fun things to do.
     
  6. Britprius

    Britprius Senior Member

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    I have fitted a 60amp/hr AGM battery the type used in mobility scooters. It is the same physical size as the Prius OEM battery with nearly double the capacity as I intend fitting an electric lift for a disability scooter. I did not wish to lift the scooter on board to find I had flattened the battery, and could not get into ready.
     
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  7. Britprius

    Britprius Senior Member

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    Do not take the easy way out and fit the smaller battery. Go with the Optima you already have.

    Check the voltage of the battery before fitting if you can. This should be around 13volts (12.9/13.1) for a well charged battery.

    There have been many reports of poorly kept Optima batteries at suppliers giving rise to batteries with voltages of 12.6 and below, not good for the longevity of the battery.

    If your battery is below the 12.6v level I would get the supplier to change it after carefully marking the battery you have (so that you can recognize it) in case they just charge it and return it to you.
     
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  8. skopstein

    skopstein Junior Member

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    OK, thanks for all the advice. I will check the Optima before installing, but at least to begin with it has a 9/12 sticker.

    I bought the car used and it was a rental. So the battery may have had a tough life. I've had it for 2 years, and this is only the second problem. (The first was that on a few occasions when I removed the key, the car did not recognize it so the warning alarm would ring. This drained the battery which could have been the sourceof my problem.)

    Any additional advice on refitting the bracket? I can cut off the bottom side lip to allow the battery to seat, but the hold-down clamp does not quite reach the hole due to the slighter higher profile of the Optima. Can I just use a bushing as a spacer, or do you recomend buying the bigger bracket from Toyota?
     
  9. PriusGuy32

    PriusGuy32 Prius Driver Extraordinaire

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    And I just got one of those Optimas (date code 3/12)! Returning it tomorrow. Highest Ive got it to read, after a 12 hour 8 amp charge is 12.75v but it quickly drops to 12.2v.
     
  10. Britprius

    Britprius Senior Member

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    Any method that holds the battery securely should be ok but the correct bracket would be the best and is not expensive from Toyota.
     
  11. skopstein

    skopstein Junior Member

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    I spent 30 minutes at the Toyota dealership today. They claim there is only one such bracket for my Gen II 2009, and that the two batteries (smart-key and non) are both the same exact size. I encouraged them to check the system, but they couldn't even find the schematic for the battery bracket. I guess I'll try another dealership.
     
  12. dorunron

    dorunron Senior Member

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    Checking online at Champion Toyota here in Houston reveals that there are two battery trays, one non sks and the other sks and only one hold down clamp. I think you need to change the battery tray to solve your problem since you are using the bigger battery now, but trying to place it in the old tray made for the smaller battery.

    If you call Jake at the 800 # listed on the site, he is very knowledgeable and can make sure you are ordering the correct part.

    Item # 8 is the part that is different. (battery tray)

    Here is the link to their site.

    2009 TOYOTA PRIUS Parts - Champion ToyotaWorld

    800-327-2087 Ask for Jake.

    Ron
     
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  13. skopstein

    skopstein Junior Member

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    Ron, et.al. Thanks for all the help. I was out-of-town this weekend and stopped by a Toyota dealership. They were able to quickly identify the battery tray I wanted (unlike my local, inept parts guy), and had it for me the following day. I installed the Optima DS46B24R this weekend (after testing the voltage, as suggested above). For anyone with a similar question, replacing the smaller tray in a non-smartkey Prius with the larger smartkey tray does indeed enable installation of the Optima.

    One interesting side issue. The first Optima I purchased from Advanced Auto Parts had reversed terminals. I had an extensive exchange with Optima about this, including pictures of the mutant battery. They eventually claimed it was mislabeled, but I couldn't find any reference on the Optima site to a DS46B24 (no R).

    FYI, Advanced is offering a 15% discount on-line off the $200 list for this battery.

    Thanks again for all the help!
     
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  14. Patrick Wong

    Patrick Wong DIY Enthusiast

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    It is great that you were alert and realized the battery polarity was reversed. Had you installed that incorrect battery, considerable damage might result to the inverter.
     
  15. gring40

    gring40 Junior Member

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    In my experience, draining the battery like that is all it takes to cripple it. Mine (original) never recovered from that, & kept failing. Toyota kept insisting it was ok, I insisted they replace it, and it's been fine ever since.
     
  16. dorunron

    dorunron Senior Member

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    Glad to hear that the different battery tray did the job.

    FWIW, Advance Auto has a code BATX which will give a $50 discount if you buy a new Optima Battery for the Prius. Just checked and the code is still working.

    Buy Optima Batteries YellowTop Battery DS46B24R at Advance Auto Parts

    Good luck to you.

    Ron