2005 - Dying Accessory Battery... wait a minute... huh?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by pumpanddump, Sep 21, 2025 at 2:50 PM.

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  1. pumpanddump

    pumpanddump Junior Member

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    No red triangle... But the usual suspects of DTC are back. Looks like i need to address the battery. However, surprisingly nothing appears for Engine...but only as INC. So its not complete? I think i need to check fuses. I already mentioned all fluids are great.

    The test drive was nothing dramatic, but up hill, down hill. Soft acceleration to hard acceleration, same for brakes. Everything seems the same. I saw no reduction in performance...for a 2005.
    The dash monitor is impossible to read, its burnt out...so no arrows.
    I forgot to do the battery monitor test in the dash, i can do that later tonight.
     

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    #21 pumpanddump, Sep 23, 2025 at 9:12 PM
  2. dolj

    dolj Senior Member

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    • P3000 means the hybrid control ECU heard from the hybrid vehicle (HV) battery ECU that it has a problem.
    • C1259 means the skid control ECU heard from the hybrid vehicle (HV) battery ECU that it has a problem.
    • C1310 means the skid control ECU heard from the hybrid vehicle (HV) battery ECU that it has a problem. It prohibits Enhanced VSC operation and a part of ECB control by the fail-safe function.
    • B1421 is a binary switch (i.e. indicates on/off) and is not a problem unless you read this code in bright sunlight. Its normal function is to tell you that it sees bright sunlight or not, and if that lines up with what happened, there is nothing wrong.
    The DTC to focus on is:
    • P3014 means battery block 4 becomes weak.
    Followed by:
    I hope that helps.
     
    #22 dolj, Sep 24, 2025 at 1:14 AM
    Last edited: Sep 24, 2025 at 1:23 AM
  3. pumpanddump

    pumpanddump Junior Member

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    Thank you, I am aware of the faults that appeared, especially the cluster guage capacitor failure it was never upgraded.

    That began after a tree branch stabbed the front of the car dashboard about 4 years ago.

    Depending on weather the dash would come back to life and besides warning lights and mph - nothing much else was accurate or useful.

    We write down when we fill the car up - after running out of gas when the tank gauge indicated it was full, use gps unit or app for speed. We have no inspection down here.
    Then for several months the dash lights all worked great.

    Now, since the accessory battery needed replacement - those capacitors drained...and its off issue( no dash light issue is back. Slowly, those capacitors are getting filled with juice by this new battery. . My dashlights will reappear again in time.
     
    #23 pumpanddump, Sep 24, 2025 at 8:24 AM
  4. dolj

    dolj Senior Member

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    That's not how this fault goes. It will progressively get worse until it fails completely.
     
    #24 dolj, Sep 24, 2025 at 8:43 AM
  5. Paul Gregory

    Paul Gregory Senior Member

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    Don't use a trickle charger. I tried that one winter, and by spring, the battery was completely destroyed.

    Use a battery maintainer instead.
     
    #25 Paul Gregory, Sep 24, 2025 at 8:56 AM
  6. rjparker

    rjparker Tu Humilde Sirviente

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    This guy does not want help and knows that a branch that stabbed his dashboard is the heart of the issue.

    Capacitors take milliseconds to charge or discharge unless they are totally bad or disconnected, but he knows that I am sure.
     
    #26 rjparker, Sep 24, 2025 at 9:33 AM
  7. pumpanddump

    pumpanddump Junior Member

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    I'm not suppose to be angered by this? I am simply replying to the one fault mentioned, and gave some background info on it. So kindly, with butterfly kisses: you have no idea what you are talking about.

    Your posts in this thread are simply to boost your numbers on here, nothing more. Please go away, you are not helpful.
     
    #27 pumpanddump, Sep 24, 2025 at 9:57 AM
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