Post broke on battery cell, now what? (need help asap)

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Domo326, Dec 25, 2023.

Tags:
  1. Domo326

    Domo326 Junior Member

    Joined:
    Feb 20, 2019
    4
    1
    0
    Location:
    Virginia
    Vehicle:
    2008 Prius
    Model:
    N/A
    Hey pplz, so I was getting the code p3013 (battery block 3 becomes weak) and decided to clean the bus bar to see if that would be the fix i need or if I needed to buy new bus bars. Well that simple job didnt go according to plan. I got 2 nuts off and on the 3rd one( i was using a power tool) the post snapped off because It didnt want to budge at first. but that thing snapped too easy, it was crazy and that wasn't even the one that was messing up( i think)(see photos) At this point it looks like i now need to buy a whole new module to replace the broken post.

    question
    1) when replacing modules, can i replace just the one thats bad ordo i have to replace both batteries that are connected in that block? Since im shooting code p3013, do i need to replace that whole block or just the bad battery of the block even if one battery is good and the other one if faulty?)

    2)which way are the banks going in a second gen Prius? I seen a couple answers online but to be clear, do I start counting from the side with the ECU or start counting from the other side that has no ECU?

    3)Were can i get a good battery from? im looking to get 2 real quick this week to get my car back up and running. I seen some being sold on amazon but dont trust it but i have never purchased a module before so need to know what to look for when looing for one as well.

    4)which bus bars should i grab from amazon? anything specific to look for? I seen 2 types but want to know which one would be the best because I seen different post saying which type of bus bars to use with different plating and stuff like that.

    5)what are the torque specs for the Bus bars, cell bolts(bolts under the cell), and compression bolts(bolts on end of hybrid battery that holds all modules together with the rails)? Im asking this because I have seen 2 numbers on each of these and want to get it right.

    6)for this code that came on, the fans kicked in and when i go to the rear of the car it smelt like burnt plastic after driving for a while. I stopped driving but wanted to see if anyone else ran into this issue. Nothing was burnt when i took everything apart though.

    Bonus question/dumb question, I always wondered what would happen if your hybrid battery stopped working or if its disconnected. I know its a stupid question and will get some smart remarks but figured Id ask anyways. Would I still be able to drive the car? Wish there was a way to hit a switch and just use the Engine in case of emergencies or something like that.

    Thanks in advance pplz. hope to get this done this week so i can use my car again.
     
    #1 Domo326, Dec 25, 2023
  2. Tombukt2

    Tombukt2 Senior Member

    Joined:
    Nov 29, 2020
    11,184
    1,953
    0
    Location:
    Durham NC
    Vehicle:
    2009 Prius
    Model:
    Base
    Generally you'll be replacing the modules with ones hopefully that are known to be good power tools on battery posts whatever kind of battery or generally a no-no that's where you use hand tools the knowledge of when to use hand and/or power tools comes from experience Good luck
     
    #2 Tombukt2, Dec 26, 2023
    Domo326 likes this.
  3. JC91006

    JC91006 Senior Member

    Joined:
    Nov 10, 2013
    16,601
    8,478
    0
    Location:
    Los Angeles, CA
    Vehicle:
    2008 Prius
    Model:
    II
    I think you snapped off the terminal on the battery module because you had your power tool to tighten instead of loosen. Also the tool you are using is probably a heavy duty tool with too much torque.

    You can easily just replace the module that's bad. That's probably a good thing that module broke, you didn't waste your time assembling everything back together just to find out that didn't fix your battery issue. You would need to replace the bad modules, not just clean the bus bars.
     
    #3 JC91006, Dec 26, 2023
    Domo326 likes this.
  4. mr_guy_mann

    mr_guy_mann Senior Member

    Joined:
    Sep 3, 2020
    3,880
    1,867
    0
    Location:
    NJ-USA
    Vehicle:
    2006 Prius
    Model:
    Four
    There is no "good" answer for you.

    Cheap, fast, and reliable. For battery repair on a Prius you usually have to choose two out of three of those.

    You want reliable and fast, get a new pack from Toyota.

    Next would be a "good used" pack from a junkyard. (trading some reliability for less cost).

    Further down is most any "refurbished" pack. Some last a few years, some have problems in a few weeks. Some cost close to what Toyota wants for a new pack.

    There's "DIY" refurbished, where you would use equipment to charge - discharge cycle modules to "improve" and equalize capacity. Less money usually needs more time to get decent results.

    Last is "just replace a few modules" (and cross your fingers). Can work but seems like maybe only 10-15% of the time, and then it usually fails again in a year.

    There are MANY posts about individual module replacement.

    The problem is that the modules degrade and lose capacity with time and use. As long as they do so evenly, then there's no real problem. When one or more modules fail (have a shorted cell), then you have a "large" voltage difference between battery blocks, and the ecu sets codes.

    When you replace a module (or 3), you can't tell what the effective capacity of the "new" ones are, or the capacity of the existing ones. A "stronger" module has higher voltage when discharging (under accel) and lower voltage when charging (decel).

    If the voltage difference between blocks is more than (around) 0.3V for more than a few seconds (?), then the ecu sets codes. The larger the difference, the less time it takes.

    The stud and nut module connections torque spec is 48 INCH pounds. Same for the module to base plate screws.

    The modules are numbered 1 (right side of car) to 28 (left side, closest to battery ecu).

    Be sure to check the orange (voltage sense harness) connector at the battery ecu for corrosion damage.

    Posted via the PriusChat mobile app.
     
    #4 mr_guy_mann, Dec 26, 2023
    Domo326 likes this.
  5. mr_guy_mann

    mr_guy_mann Senior Member

    Joined:
    Sep 3, 2020
    3,880
    1,867
    0
    Location:
    NJ-USA
    Vehicle:
    2006 Prius
    Model:
    Four
    Additionally, the hybrid drive system is integral to starting the engine or moving the car. Without the HV battery, you have a 4 wheeled paperweight.

    Posted via the PriusChat mobile app.
     
    #5 mr_guy_mann, Dec 26, 2023
  6. TMR-JWAP

    TMR-JWAP Senior Member

    Joined:
    Aug 12, 2016
    6,404
    6,073
    0
    Location:
    Columbia, SC
    Vehicle:
    2007 Prius
    Model:
    Touring
    Unfortunately, you tore into this with little or no knowledge of what you were getting into, along with lack of preparation. You would be better off calling a $400 craigslist repair guy to replace your battery. I don't see this ending well.
     
    #6 TMR-JWAP, Dec 26, 2023
  7. Domo326

    Domo326 Junior Member

    Joined:
    Feb 20, 2019
    4
    1
    0
    Location:
    Virginia
    Vehicle:
    2008 Prius
    Model:
    N/A
    This is true, I didn't go in with all the knowledge needed for this project but it turned out to be a happy accident. It forced me to learn everything about the hybrid system in the car and I am well versed now. So all turned out well in the end.
     
    #7 Domo326, Dec 31, 2023
  8. Domo326

    Domo326 Junior Member

    Joined:
    Feb 20, 2019
    4
    1
    0
    Location:
    Virginia
    Vehicle:
    2008 Prius
    Model:
    N/A
    UPDATE:
    Vehicle is back on the road! Man I learned a lot from this experience/mistake. If i would have never broken the post of the battery, I would have never did the amount of research needed to figure out how the whole hybrid battery system works on the Prius. With the help of other very helpful people (that im grateful for), it was determined that it wasn't the batteries at all. It was the computer connected to the hybrid battery and the bus bars that connected to the computer that needed to be replaced. Now all my codes are clear and I now know the importance of using a hand tool over using power tools for more delicate jobs lol

    Now ill be trying to load test each individual battery to determine which cells are good and going bad. That will be way later but glad I found the process on how to do that as well.
     
    #8 Domo326, Dec 31, 2023
    bisco likes this.
(You must log in or sign up to post here.)