MID warning message: Low Battery Turn Power Off

Discussion in 'Gen 5 Prius Care, Maintenance and Troubleshooting' started by chrisrappl, Dec 6, 2025.

  1. chrisrappl

    chrisrappl Junior Member

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    Sorry to post here, but the Camry forum is not the same caliber as Prius Chat.
    I have a 2025 Camry LE which has the 5th gen hybrid system and Safety Sense 3.0 so hopefully very similar to the new Prius models.
    When I finish a drive and turn off the vehicle by pushing the power button some systems naturally stay active until I open a door to exit.
    If I shut down the vehicle and stay seated without opening a door, after 60 seconds I get a chime and a warning message in the MID - Low Battery Turn Off Power.
    Is this normal?
    How would I shut off power if I already turned the vehicle off?
    If I open a door, the message goes away.
    I checked the 12v battery and proved that it charges in ready mode.
    Toyota seems to not keep these 12v batteries fully charged since they do not have a starter motor draw on them. I know this from my 4th gen Prius Prime.
    Thanks
     
    #1 chrisrappl, Dec 6, 2025
  2. BiomedO1

    BiomedO1 Senior Member

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    IMHO; you should either change the default settings or pop the door when you shut-off the car. I have a similar option in my GMC, radio and other stuff doesn't power-down until I pop the door. The last time I was in there, I changed those defaults to shut-down with the key-OFF. The only thing I left ON was perimeter and interior lamps, when unlocking and locking the car - set to remain ON for 30 seconds. All of my lamps was changed to LEDs so minor current draw.
    When you checked your battery; did you do a voltage and current draw test? You can have good voltage but bad current draw on that battery, which the dealership should replace under warranty within the first year.

    Good Luck....
     
    #2 BiomedO1, Dec 6, 2025
  3. chrisrappl

    chrisrappl Junior Member

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    BiomedO1,
    Thanks for the reply. I did measure the CCA performance.
    Here is what I think I know so far:
    With the battery at its normal (low) state of charge it takes exactly 60 seconds after shutting off the vehicle for the "Low Battery Turn Power Off" warning to appear in the MID.
    The owner's manual does not list this exact warning message, so no help there.
    I believe that this warning message "Low Battery Turn Power Off" concerns the 12v battery, but I'm not absolutely sure.
    My 12v battery measured 11.69v which is very low.
    But even at 11.69v, the 345 CCA rated OEM battery tested at 484 CCA.
    CCA is measured at 0 deg. F and my garage is warmer at about 45 deg. F, so it should test higher.
    After charging for 140 minutes at approximately 3 amps, the voltage registered 12.43v (so not fully charged yet) and the CCA tested at 622a.
    With this much higher state of charge it still takes exactly 60 seconds after shutting off the vehicle for the "Low Battery Turn Power Off" warning to appear in the MID.
    With the car in ready mode, the voltage tests at 14.33v, so the system is definitely charging the 12v battery properly.
    I will test again when the battery is fully charged, but I don't think that there is a problem.
    My 2017 Prius Prime 12v battery voltage always tests low. My tester always tells me to recharge and test again.
    The 12v battery is able to be charged by the traction battery whenever the car is in "ready" mode.
    I have to believe that Toyota made a conscious decision to not keep the 12v battery in a high state of charge.
    Since there is no starter motor high amperage load, it may not be necessary.
    Just like we don't keep our traction battery fully charged for extended periods on the plug-in hybrids, maybe they decided that the lower state of charge might extend the life of the 12v battery?
     
    #3 chrisrappl, Dec 6, 2025
  4. Prodigyplace

    Prodigyplace 2025 Camry XLE FWD

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    After a year with my 2025 Camry XLE I can state that is definitely NOT normal. I think you got the same answer over at ToyotaNation.
     
    #4 Prodigyplace, Dec 6, 2025
    soft_r likes this.
  5. BiomedO1

    BiomedO1 Senior Member

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    I hate to say this but your battery tester is highly suspect and probably as accurate as a random number generator. I'm more inclined to use an old fashion carbon-pile load tester. It won't generate random numbers that the instructions explain in a convoluted manner. It simply shows how a very heavy load will effect the battery and how many volts it can steadily output while sustaining that high discharge load. Basically what a battery should be doing under high stress. Results matter, not random numbers.

    It sounds like you've already made up your mind, so just ignore the warning......
     
    #5 BiomedO1, Dec 7, 2025
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