1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Replacement of 12 volt auxiliary battery

Discussion in 'Gen 2 Prius Main Forum' started by dzitlow, Jun 24, 2005.

  1. seeh2o

    seeh2o Prius OG

    Joined:
    Mar 5, 2004
    447
    16
    0
    Location:
    City of Angels
    Vehicle:
    2013 Prius
    Model:
    Persona
    Thanks so much, Ron. I'm stuck in Las Vegas right now. Back home in Los Angeles, I have the BEST guy who works on my car...if I didn't have the dogs with me, I'd have had the battery jumped and just driven straight to his place and he would of changed it out for me on the spot. I talked to him this morning, he thought it would be safe to do it that way, but again, I'm more concerned about the dogs. I won't melt and overheat, but they might!
     
  2. dorunron

    dorunron Senior Member

    Joined:
    Jul 17, 2011
    3,318
    1,104
    0
    Location:
    Houston, TX
    Vehicle:
    2013 Prius
    Model:
    Three
    I hear ya, if you are forced to make the trip do so without shutting the car down. Jumping a Prius is very risky. If you ever get the cables reversed, you are looking at a four digit repair bill. The Prius will run Ok as long as it is in ready mode with a bad battery. The worst that could happen would be your mileage to suffer if you have a dead cell. Get a new battery as soon as possible. Good luck to you.
     
  3. seeh2o

    seeh2o Prius OG

    Joined:
    Mar 5, 2004
    447
    16
    0
    Location:
    City of Angels
    Vehicle:
    2013 Prius
    Model:
    Persona
    While I was in the parking lot at B, B & B, a woman walked by and asked what happened. I told her the little battery died. She said the same thing happened to her daughter last night and she had to have it towed to a shop. Then, this afternoon I found out that a friend of mine back in LA had the same thing happen to her Prius yesterday.

    Could the unseasonably hot weather be wreaking havoc on weak 12 volt batteries?
     
  4. dorunron

    dorunron Senior Member

    Joined:
    Jul 17, 2011
    3,318
    1,104
    0
    Location:
    Houston, TX
    Vehicle:
    2013 Prius
    Model:
    Three
    Unfortunately, a 12 volt battery always seems to die at the worst time. With the Prius there really is no warning signs like a slow cranking engine. What usually happens is the electronics start acting funny and sometimes the red triangle will appear when you first go into ready mode. But yes, heat can kill a battery just as much as cold temp can kill one too. All batteries have a life span. Sometimes they just last a little longer than others, but eventually they will have to be replaced.

    One thing that helps on the Prius is this test you can run. Take a look at this string.

    Weird stuff happening? MPGs dropping? Test The Battery | PriusChat

    Ron
     
  5. Britprius

    Britprius Senior Member

    Joined:
    Jun 14, 2010
    5,194
    1,917
    0
    Location:
    Herefordshire England
    Vehicle:
    2008 Prius
    The AH capacity of the battery has no bearing on it's day to day running of the car, but in terms of reliability the higher the AH capacity the better. If it were the case of using the correct AH battery the Optima would be a no go as it is lower than the OEM battery.

    John (Britprius)
     
  6. Nakedinthewind

    Nakedinthewind New Member

    Joined:
    Jul 16, 2014
    1
    0
    0
    Location:
    Bishop, GA
    Vehicle:
    2006 Prius
    Model:
    N/A
    StreetSideAuto.com, LLC
    http://www.streetsideauto.com/
    [email protected] 877-787-8989

    Optima 8171-767 - YellowTop; Deep Cycle Battery
    $147.05 + Free Shipping

    It is a direct fit. I just installed mine today....
     
  7. AvTech72

    AvTech72 Junior Member

    Joined:
    Sep 4, 2019
    28
    1
    0
    Location:
    Miami Beach, FL 33140
    Vehicle:
    2008 Prius
    Model:
    Three Touring
    Hello I know this is an old post, but it seems Toyota does not have original OEM 12v aux battery # 28800-21170.
    Any suggestions where to find it, or just go with Bosch replacement?

    Posted via the PriusChat mobile app.
     
  8. Georgios

    Georgios Member

    Joined:
    Feb 6, 2018
    126
    85
    0
    Location:
    Chicago
    Vehicle:
    2008 Prius
    Model:
    ----USA----
    Advance auto with 20 online coupon and $22 refundable core its total for around $177 and that is AGM Battery. They also have much cheaper "silver" which could be ok or very good or very bad. Some of the advance auto battery for german cars are made in germany and last long time.
    Alsto the post before was stating the exact part number of the Optima.
    Walmart probably has some options too, Autozone, Napa...
     
  9. Stevewoods

    Stevewoods Senior Member

    Joined:
    Jun 10, 2014
    651
    1,023
    0
    Location:
    Seattle, WA
    Vehicle:
    2008 Prius
    Model:
    II
    And, you can get a real Toyota with a great warranty for $20 more.
     
  10. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    110,133
    50,050
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    try another dealer, or the bosch is fine
     
  11. Beshara1111

    Beshara1111 Junior Member

    Joined:
    Jul 6, 2011
    57
    5
    0
    Location:
    USA
    Vehicle:
    2008 Prius
    Model:
    N/A
    I had purchased the 12V31M Westco elsewhere and went to a few auto stores getting post adapters, a new negative cable, vent tubing, and fashioning wood blocks for making the hold down work, and would have rather have had a kit like the above had I known about it.

    The elearnaid site now appears to sell a Deka battery instead of the Westco. I don't know how to compare performance, but it is also a Miata replacement. The site recommends an Optima battery replacement, but many comments on different sites claim Optima quality is no longer consistent...
     
    #111 Beshara1111, Mar 4, 2021
    Last edited by a moderator: Mar 5, 2021
  12. uclabruins

    uclabruins Member

    Joined:
    Jan 31, 2006
    265
    5
    0
    Location:
    City of Angels, Baby!
    Vehicle:
    2006 Prius
    Model:
    N/A
    What's the best 12V battery to replace with these days if not Optima Yellow Top? OEM? Thanks in advance.
     
  13. sam spade 2

    sam spade 2 Senior Member

    Joined:
    Mar 31, 2018
    7,035
    2,790
    0
    Location:
    USA
    Vehicle:
    2017 Prius c
    Model:
    Four
    OEM.
    But right at the moment, the best answer might be: Whatever direct replacement that you can find.
    "Piece parts" for a LOT of things are scarce at the moment.