P3007 - Module 7 Becomes Weak - Opinions?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Gp1138, Jul 21, 2025 at 11:33 AM.

  1. Gp1138

    Gp1138 New Member

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    So, I have resolved most of the issues on my basket case $800 2007 Prius. The only remaining one that affects driving is as follows: when I start driving in the morning, the car is fine until about a half hour into the drive, it throws a P3007 for "Module 7 becomes Weak" - I have taken some TechStream recordings and it indeed seems to drop intermittently. Sometimes I can drive miles and it doesn't come on. The battery appears to hold a charge, doesn't drop like mad when I hit the gas, and sometimes even charges up to almost fully green. But it will pretty reliably throw the code every 10-20 minutes, especially if I am on the freeway.

    When this happens, I have pretty much just cleared the code and continued driving as I am usually not in a spot where I can stop. It never throws another code, so I am basically going to get another battery module and replace it when I get a few days to let it sit, but at the moment it is basically a daily. How long can I ride this out until I can replace the module?
    The battery, by the way, was claimed to be just replaced. The battery was "reinstalled" with the barest of fasteners and care - the driver's side body mount for the pack is sitting loose and the red cover was barely fastened down. I took the cover off and the busbars appear to have been replaced with silver ones. I took an IN-lb torque wrench and several of the nuts had a half turn in them before it clicked at 45in-lb. It doesn't behave any differently after I did this, though I did not really suspect it would and I did not pull the cover entirely off to check the rearward-facing ones.

    There are stickers from a local shop all over the battery - whom I called and they said I can't get any warranty service without the receipt from the previous owner, who took the documentation out of the car before I was able to pick it up after we switched the title, and will not return my messages. Which, OK, whatever. I can fix it myself cheaply, like I did all of the other stupid crap that was miswired and poorly reassembled. But in the meantime, am I going to cause serious damage if I just continue to clear the code and drive the car?
     
  2. Tombukt2

    Tombukt2 Senior Member

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    Block 7 becomes weak a block is two modules. You'll be replacing two modules or block 7 completely.
     
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  3. bisco

    bisco cookie crumbler

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    no, not until it dies completely or catches on fire
     
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  4. Gp1138

    Gp1138 New Member

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    Thank you for the info, I will purchase two modules in that case.
     
  5. Brian1954

    Brian1954 Senior Member

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    Take one step back before replacing any battery modules. Code P3007 is Not for "Module 7 becomes Weak". Maybe you made a typo, and the correct code is P3017, which is "Module 7 becomes Weak". The other thing that does not make any sense is that you say that you do not have any other codes. Well, you first need an active code P0A80 before code P3017 will be triggered. If you have code P0A80, you should look at the freeze frame data for that code in Techstream and see which battery block voltage is not like the other battery blocks.
     
  6. Gp1138

    Gp1138 New Member

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    Yes, I got that code wrong. I will update the OP later.
     
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