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12 volt battery dead

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by BobA, Nov 1, 2009.

  1. BobA

    BobA New Member

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    it's been a while since I posted here.. I love my Prius and hav had NO problems.. until today

    ok that said I know there is a member of the group who knows how to fix my
    dilemma... I went to the store and came home.. parked in the drive way as I
    needed to fix a light in the opener.. I did that and went back to the car.. foot
    on the break I pushed the Start button... NOTHING.. no lights on the dash.. I
    hit the button again... the shift pattern and gas gauge blink.. another push on
    the start button and the light in the parking break button blinks.. I know it's
    Halloween .. but my Prius is haunted... and Saturday as well.. I quickly called
    my dealer and talked to a service guy.. he agreed with my thought that I have a
    dead battery.. my Prius is an '04... this was at 3 something.. knowing that I
    had until 5 before the dealer closed and chose to just have it towed to them.. I
    don't need a car until they came in on Monday and thought the car would be
    better there than in my driveway.. since the driveway is on a slope I thought I
    really couldn't push it.. the tow arrived the guy said 'will it roll?' duh I
    hadn't thought about that.. nope.. I know you all know that.. he said he'd call
    for a hook truck.. with my window of having a person at the dealer to receive
    the car I said no.. I called the dealer and found that they did have a battery
    in stock.. I decided that I could go and get a battery and put it in myself.. I
    was sold a battery.. in a 2 foot cube box.. which I haven't opened.. I got home
    looked at the book and am not sure that I know where where the battery really
    is.. I went to the back of the car removed everything and got to the spare..
    removed the cover on the right side and think I'm seeing the battery.. that is
    as far as I got.. not sure how to proceed..



    my questions are..



    am I at the battery?

    is it a job for a novice?

    is there a way to unlock the transmission and move the car?

    because the garage is in front of the car I can't see how they get the hook on
    it..

    and lastly.. I locked all doors.. now is there a way to open the hatch?



    I know you all are all are a knowledgeable group.. and am sure this has happened
    to at least one of you.. if you are in Denver and can help hands on I'll take
    any I can get.. PLEASE help me

    Bob
     
  2. djasonw

    djasonw Active Member

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    I have the same year Prius and my car's 12v battery died primarily due to neglect. I had the car in storage and my friend was supposed to drive it every few weeks but there were times he wasn't able. Long story short, the battery finally died and would NOT take a trickle charge. My friend did the installation and it is a little tricky if you're not that handy (I'm not). The battery is in the rear hatch passenger side. If you feel uncomfortable doing it, just bring it to a reputable mechanic. He'll probably have it done in 1/2 hour.

    What did Toyota charge you for the battery? I bought mine online from a dealership in the midwest and with shipping it was less than $120.
     
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  3. BobA

    BobA New Member

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    thanks djasonw.. I drive the car almost every day.. it isn't due to a lack of driving.. I don't think.. I haven't done any maintence to it either.. I think my dealer charge was $130.. I didn't argue or price shop.. some how thought it would be an easy fix.. bought a battery for my '51 nad was running in about 15 minutes..
     
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  4. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Hi Bob,

    $130 is a good price at the dealer.

    You are in the vicinity of the 12V battery. Can you see the red plastic cover over the positive terminal of the battery?

    To get into the hatch, you have to unlock the driver's door with the mechanical key hidden in the fob. Then crawl into the hatch. Remove the folding hatch panel and the black plastic tray on top of the spare tire. Find the little lever that will unlock the hatch lock on the hatch floor. Then you can raise up the hatch.

    There is no way to unlock the parking pawl in the transaxle, without first restoring 12V power to the car.

    You'll need a set of metric sockets (10, 12 mm sizes) and a ratchet wrench. You'll also need a box wrench to remove the battery terminal connectors (9mm or maybe 10 mm, I forget which).

    You will have to remove the traction battery ventilation duct that runs over the 12V battery, and also remove the brake power supply that is next to the 12V battery, in order to gain access. No need to remove the wiring harness connector that attaches to the power supply.

    Once you get to the 12V battery, you'll have to remove the battery cable negative terminal where it attaches to the body of the car (easier than trying to remove the cable at the negative terminal) and then lift up the red plastic cover while removing the positive terminal connector. Then remove the 12V battery bracket. The positive terminal connector and fuse block are attached to the bracket with a plastic pin, you can remove both parts as one assembly.

    Work carefully and pay attention to what hardware is coming from what location so that you can replace everything. Note how much force you are using to remove the hardware and try to exert similar force when tightening. Good luck.

    BTW, to reduce the incidence of emergencies such as the one you've faced, I suggest owners should replace their 12V battery based upon time in service rather than wait for a failure.
     
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  5. BobA

    BobA New Member

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    thanks Patrick.. I always forget the battery.. both here and my '51.. I watch the fluids but never think of what else is making the car run.. so much for being a Gear Head or in the case of the Prii.. a Gear Techie..

    Bob
     
  6. alanh

    alanh Active Member

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    If you don't want to climb into the back area, you can also jump start the car from the jump point under the hood. Once the car is started, you can open the hatch as normal.
     
  7. tedroberts

    tedroberts Junior Member

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    My 2005's 12 volt battery got a dead short after about a year. Toyota replaced it under waranty.
     
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  8. PA Prius

    PA Prius Active Member

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    Thanks for this detailed description. What is the suggested "time in service"? Our original 2004 12v battery was dead this morning. No lights were left on. Of course I didn't notice whether the driver's door was possibly ajar. I did the battery check and it came up a few tenths short on all three test modes, so I'm not sure if that is serious or not.

    PA P
     
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  9. JimN

    JimN Let the games begin!

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    I replaced the 12v battery after 3 1/4--3 1/2 years when it wouldn't start as a preventative measure so I wouldn't get stranded in NY. The replacement lasted ~6 weeks before failing at the office. I recommend checking the voltage regularly.
     
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  10. hill

    hill High Fiber Member

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    It's been posed time & time again ... the OEM aux battery is NOT designed with cranking amps in mind. If you get 3 or more years out of it ... consider yourself very lucky & replace it NOW. Replace it with the optima ... which has also been re-posted on PC, ad nausium. With the yellow-top installed, you'll never look back.

    ;)

    .
     
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  11. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Since you live on the East Coast with frigid winters, I'd say that four years would be a good service life. You did quite well to eke out six years.

    I assume that you drive the car enough to keep the battery charged up - my guess is that the car is driven almost daily, and has logged >=10K miles per year?
     
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  12. kdmorse

    kdmorse Member

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    I just stopped by to see what the expected life of the 12v battery would be, as I think mine's starting to get a bit twitchy in this weeks bitter cold. It's now four years old (exactly, to the day) - and my 2006 had problems starting yesterday. One system startup just seemed somewhat unsmooth, as if it couldn't make up it's mind. It christmas-tree-of-doomed for a second, then started up on it's own. Then later that day it refused to start up on the first attempt at all.

    I killed it once while it was young while tinting the windows, and the symptoms seem identical. Flashing transmission indicator, fuel gauge alternating between full, and flashing one pip, all lights lit up - doesn't want to power off, but doesn't want to power up either.. seems to be a dead ringer for insufficient 12v current...

    But I couldn't for the life of me remember if 4 years of life was longer than expected, or shorter than expected. But it sounds like I did well, and it will get replaced tomorrow....

    (Turned off SKS in the meantime)

    -Ken
     
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  13. richard schumacher

    richard schumacher shortbus driver

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    Unless $200 is nothing to you, you should test the battery first. It might save some expense or trouble.
     
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  14. Sandy

    Sandy Hippi Chick

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    I had all kind of gremlins until i replaced mine at 5.5 years
     
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  15. Patrick Wong

    Patrick Wong DIY Enthusiast

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    I would say that a battery "test" is reliable to the extent that if you determine the battery is bad, it probably is.

    However, if you rely on a voltage test or a load test to determine the battery is good, your test might be lying to you.

    The best "test" is to fully charge the battery, then put it back into service. If you continue to have problems, then replace the battery and be done with it.
     
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  16. kdmorse

    kdmorse Member

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    I didn't stumble upon the thread with test instructions on it until later this evening - had no idea that function was in the maintenance menu. (Haven't given that menu a second glance in over 3 years). Neat!

    Unless I did something completely wrong - 10.2 volts cold. 14.4 volts running. And it started indecisively again this evening. I draw the conclusion that it's not holding a charge well, may have been borderline for some time, and this weeks bitter cold was the last straw.

    -Ken
     
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  17. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Hi Ken,

    A reasonable conclusion, as long as you've been driving the car enough so that the battery has had plenty of opportunity to be charged.
     
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  18. jdenenberg

    jdenenberg EE Professor

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    Ken,

    A reading of 14.4v running is too high! Check it again and if it is really that high get the charging system checked out a dealer. A high charging voltage can cook our little 12v batteries.

    JeffD
     
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  19. famtruss

    famtruss New Member

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    I hate to say it, but when it's 15 degrees and the only set of jumper cables available have clamps that are too big for the horribly undersized (+) terminal it makes it a real pain to get that thing hooked up. On top of that, in the dark it's difficult to find a good (-) point to hook up the negative terminal.
     
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  20. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Regarding the + terminal, maybe if you connect a paper clip or alligator clip to the dedicated jump start terminal, then you can clamp the jumper cable to the clip.

    Regarding the - side, use one of the nuts that secure the top of the driver's side suspension strut.