2009 12 volt battery depletion

Discussion in 'Gen 2 Prius Technical Discussion' started by crochambeau, Dec 13, 2025 at 7:26 PM.

  1. crochambeau

    crochambeau New Member

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    Location:
    Pacific Northwest
    Vehicle:
    2009 Prius
    Model:
    N/A
    2009 Prius, started eating through 12 battery charge about a month ago.

    I measured around 1.065 amps of draw on the 12 volt battery after sitting for around ten minutes after a solid drive today. The battery had been charged up, disconnected, and left alone for around a week prior to today's travels, and the battery held that charge just fine (so I'm not thinking bad battery yet).

    While the car if off and sitting, I pull and replace fuses in the engine compartment until I hit one that instigates a substantial drop in current, down to around 100 mA (I feel like that is still a touch high, but, baby steps..). That fuse is labeled "DOME" and I've seen reference to it so I think to myself "awesome, we can live without the dome light, case closed!"

    Button the car up, test for power - nothing. No dash, no wake up, no functional car.

    I replace the 15 amp "dome" fuse, car starts up just fine.

    This car is also recently experiencing a display issue in which the MFD mostly just shows white with some vertical lines (but the touch functions still work if you manage to hit the correct spot) in case this might be related.

    Ideas?