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Fixed leak in hatch and cleaned bus bars, still no worky

Discussion in 'Gen 2 Prius Technical Discussion' started by opivy224, Jun 28, 2020.

  1. opivy224

    opivy224 Junior Member

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    Hey dudes, I really appreciate all of you.

    I discovered I had the notorious leak on the top of my hatch in my 2009 Prius with 167k miles. I had gallons of water in my wheel well and battery well for presumably many months.

    My bus bars were heavily corroded, and I was getting a low voltage error and the red triangle of death. I later discovered the plug on the battery harness that goes into the battery control module and the module itself was fried.

    I took my battery apart and cleaned all the bus bars and had to order a new (used) ECU and harness that goes on the rear seat side of the battery. I stupidly bought the harness from eBay and ended up getting one out of a Prius with water just like mine. It was pretty corroded but I think I cleaned it up and it looks okay screwed but I'm worried about all the fragile contacts and wires that are still a little corroded. I ended up stripping one of the posts on a battery module. Will it work if the nuts either side of it are tight?

    I buttoned it all back up anyway and put the safety plug in and started it up, now I'm getting a battery isolation fault code P0AA6. I have included some pictures, maybe somebody can tell me if I hooked something up wrong or what I should test. Also I'm guessing I need to replace the module whose post I stripped. I do have a grid charger hooked to the positive and negative terminals on the battery, in case you notice the extra wires.

    What i havent done yet is test the modules under
    load. I did notice some blue liquid on one or maybe two modules, but thought it was just from the moisture and blue corrosion.
     

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    #1 opivy224, Jun 28, 2020
    Last edited: Jun 28, 2020
  2. TMR-JWAP

    TMR-JWAP Senior Member

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    Do you see all the corrosion at the bottom of the Block 2 modules? That is an electrolyte leak, probably from the bottom of module #4 from the end.

    The corrosion you see is not due to water. It is normal corrosion that occurs on those copper bars and voltage sensing tabs. It varies slightly based on the environment the car is in, but it's present on every battery.

    yes, you are missing a fastener on the same #4 module, but on the end opposite the leak. At least you stripped threads on a module that is likely already bad. No..your battery will NOT work without that fastener. I'm not trying to be a jerk, but if you're even asking that question, you do not have the knowledge or skills to be safely working on an HV battery. You are at significant risk of damaging the battery or yourself. You may want to think about that.
     
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  3. opivy224

    opivy224 Junior Member

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    Thank you for the reply, I may be in over my head but I am learning. I do take safety precautions when working on the battery and i kind of knew trying to operate it with the missing nut was dumb. I ordered a 1/4 inch torque wrench to properly secure the nuts and I ordered modules. I am fairly confident that I will get this fixed without harming myself or the battery any further. I do appreciate your help and your concern though.
     
  4. opivy224

    opivy224 Junior Member

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    Good catch pointing out that corrosion under the battery. I would not have put two and two together. It certainly does look like it was caused by that module. Is it best to replace both modules in a block? Also do you know if the Maxx volts grid charger will balance a battery the same way doing it manually with individual modules does? I originally thought my Prius sat too long and the hv battery was in a state of deep discharge. I realized that wasn't the case before they shipped my grid charger, but they refused to cancel my order. So id like to use it if I can.
     
  5. therakeets

    therakeets New Member

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    Hello, I balanced my batteries, did not last, i cleaned the wires, . did not last. I want to replace the hv wire harness, plug, 1 has sticker 47071, its the one in the last pic opi posted. I can not find the part using the number. What is it called and can i buy it new somewhere? I would like to try this before replacing the whole battery system. thank you
     
  6. TMR-JWAP

    TMR-JWAP Senior Member

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    Unlike the Gen 2 , the gen 3 wire harness is not available for purchase separately from the battery.
     
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