Please help

Discussion in 'Gen 2 Prius Main Forum' started by Ajj, Jan 27, 2026.

  1. Ajj

    Ajj Junior Member

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    Please help c1241 code

    ✳️✳️ Update the local garage told me it HV traction battery problem. And he told me he had recalibrate the battery because the cells were not even, some 80 % and some 50%. He did this by using a snap on scanner only. And it took approximately 30 minutes. Is this possible I paid him for the work.



    As I drove out of the garage. The braking system light re appeared. Thanks for looking everyone. IMG_1240.jpeg IMG_1229.jpeg
     
  2. ChapmanF

    ChapmanF Senior Member

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    I think I would not return to that garage. C1241 is not about the traction battery, and there is no traction battery 'recalibration' that balances the modules in half an hour using only a scan tool.
     
    pasadena_commut and Brian1954 like this.
  3. Ajj

    Ajj Junior Member

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    Hi thanks for your reply. He insisted that he balanced the battery via a snap on scanner. It may have been one hour. Do you think the the 12 volt battery that needs replacing.
     
    #3 Ajj, Jan 27, 2026
    Last edited by a moderator: Jan 28, 2026
  4. ChapmanF

    ChapmanF Senior Member

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    He can insist all he wants; there's no scan tool function to 'balance' a traction battery that I know of. Not in half an hour, not in an hour.

    So far, I can't say what "needs replacing", if anything. It sounds like you have a C1241 code. You can search for C1241 on this page, and you'll get the basic idea what things can cause it and where to start looking:

    Blink (a/k/a Flash) Codes – How to. | PriusChat

    Fixing or replacing anything comes after finding the cause of the problem.
     
  5. Ajj

    Ajj Junior Member

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    Thank you
     
  6. highmilesgarage

    highmilesgarage Active Member

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    the 2nd gen Ford Escape Hybrid has that balancing feature using a scan tool (Forscan) but I don't think any Toyota hybrid has that. Your mechanic just basically screwed you..
     
  7. PrimalPrius

    PrimalPrius Junior Member

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    Those codes are both from ABS/VSC/TRAC because it is seeing a 12V battery voltage that is too low. (Neither is about the HV battery).
    First step is to charge your 12V with a battery charger. Keep a jump pack with you if you have one.
     
  8. qmanqman

    qmanqman Active Member

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    FYI, "Traction Battery," if you wanna call it that, rebalancing takes 3 days using an $800 tool
     
  9. PrimalPrius

    PrimalPrius Junior Member

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    Actually, I should have written: C1241 is caused by the battery. C1249 could have a "real" cause.
    First I would ensure that battery is good, clear codes, verify that brake lights work, and see if the code comes back.
     
  10. dolj

    dolj Senior Member

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    Maybe, but there can be other things to check. Specifically, C1241 is about low/high voltage arriving at the B+ terminal of the skid control ECU. Everything on that path from the 12 V battery to B+ is suspect until ruled out.
     
  11. PrimalPrius

    PrimalPrius Junior Member

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    Correct, but battery should be most common cause. I think that the part missing from the quote is the correct next step for most people: "First I would ensure that battery is good, clear codes, verify that brake lights work, and see if the code comes back."
     
    #11 PrimalPrius, Feb 12, 2026 at 12:20 AM
    Last edited: Feb 12, 2026 at 12:26 AM
  12. dolj

    dolj Senior Member

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    Another thing to bear in mind is that C1241 is often set while driving. Theoretically, the battery is not in the loop once the car is READY.

    The point I am trying to get across is that this code simply is not caused by the battery as was stated up thread. This code is far more nuanced.

    The first step with any code that involves voltage received is to check the power supply. The repair manual test is to check the 12 V battery voltage, and (usually) if it is above 10.5 V, then move on to the next step.
     
  13. Ajj

    Ajj Junior Member

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    Thank you I bought a new 12v