1. Attachments are working again! Check out this thread for more details and to report any other bugs.

New 12v battery, low readings

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Ryan Romaine, May 15, 2019.

Tags:
  1. Ryan Romaine

    Ryan Romaine Junior Member

    Joined:
    May 15, 2019
    6
    1
    0
    Location:
    California
    Vehicle:
    2008 Prius
    Model:
    N/A
    Car died past two days in a row. Had to jump and just.got a new 12v. This morning it's showing I'm as low as 11.3-11.4 volts in standby, and 14ish in ready. Any idea ? I can't afford this stuff, man
     
  2. SFO

    SFO Senior Member

    Joined:
    Feb 7, 2017
    5,302
    4,241
    0
    Location:
    Northern California
    Vehicle:
    2007 Prius
    Model:
    N/A
    Welcome to PriusChat!!

    Always keep the vehicle "Ready" or "Off", that way the battery doesn't drain.

    How many hours per week do you drive this vehicle?

    Where was the 12v purchased, as the battery should still be under warranty.

    Ask the retailer if they charged it before the sale, or just charge it yourself.
     
  3. exstudent

    exstudent Senior Member

    Joined:
    Jul 11, 2009
    2,214
    902
    0
    Location:
    Torrance, CA
    Vehicle:
    2007 Prius
    Is my inverter coolant pump slowly failing? | PriusChat
    Read Post #5 (how to apply a load for a more meaningful measurement of 12V battery health)
    Read Post #8 (Battery SOC (State of Charge) chart and 12V AGM compatible smart chargers to consider buying).​

    Is there an aftermarket accessory that is draining the 12V battery?
    Was the dome or map lights left on?
    Was a door left ajar overnight?

    Deactivating SKS will drain the less. But, sure beats the convenience of having SKS.
     
  4. Ryan Romaine

    Ryan Romaine Junior Member

    Joined:
    May 15, 2019
    6
    1
    0
    Location:
    California
    Vehicle:
    2008 Prius
    Model:
    N/A

    Not to my knowledge. The car was used, and all I can tell is some tint. Rest seems stock. I don't remember turning anything on, but will keep notice. Mechanic said after a week If the battery is dead again there must be something draining it.
     
  5. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    110,129
    50,045
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    disconnect the 12v negative. measure the voltage at night, and again in the morning