code 612/526, swap an old battery?

Discussion in 'Gen 2 Prius Main Forum' started by Raghav, Apr 27, 2026 at 3:44 PM.

  1. Raghav

    Raghav Junior Member

    Joined:
    Mar 11, 2013
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    Vehicle:
    2006 Prius
    Model:
    N/A
    IMy prius has 612/526 code. I have 2 questions

    1. Is it always the hybrid battery? Can it be something outside battery too?

    2. If it is hybrid battery, I have a spare in my garage. It was pulled from a totalled prius, bought at junkyard. But it has been sitting there for about 5-6 years. Is it still usable or would it have degraded to a point of no return?

    If old battery is not usable, what are some tips to diagnose the 612/526? I have the pdf, but it is a bit daunting, and wanted to know if there are some common things ( I read somewhere about "goop on the bottom" that can be wiped clean) that I should look for before getting into full blown diagnostics.

    At the end, is it worth all this or just buy a reconditioned battery and hope it will last few years?

    Thanks in advance.