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Smart Key won't work even with new battery

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by turbo5spd-prius, Jun 29, 2024 at 8:23 PM.

  1. turbo5spd-prius

    turbo5spd-prius Junior Member

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    My car wouldn't start unless I put the fob in the dash insert. I replaced the battery but it still won't work without being in the dash.

    The old cell, less than a year old is 3.1V. The new is 3.3V

    What might I be missing?
     
  2. bisco

    bisco cookie crumbler

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    does the fob light come on when you press a button?

    how is the 12v health?
     
  3. turbo5spd-prius

    turbo5spd-prius Junior Member

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    The 12V battery seems fine at 12.6V measured under hood.
     
    #3 turbo5spd-prius, Jun 29, 2024 at 8:36 PM
    Last edited: Jun 29, 2024 at 8:44 PM
  4. turbo5spd-prius

    turbo5spd-prius Junior Member

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    The light does flash on the fob. I measured 12.6V under the hood between the jumper terminal and chassis.

    I guess I'll add that the remote locks work fine, just no proximity functions (button on door, starting without it in the dash).
     
    #4 turbo5spd-prius, Jun 29, 2024 at 8:43 PM
    Last edited: Jun 29, 2024 at 8:48 PM
  5. Tombukt2

    Tombukt2 Senior Member

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    Have you replaced the case that's on the fob did you forget the transponder chip?
     
  6. turbo5spd-prius

    turbo5spd-prius Junior Member

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    No, I hadn't. I just found the problem. Apparently I accidentally hit the "key" button under the dash recently fumbling for the hood latch at night.

    Solved.

    Thanks everybody for your input.
     
  7. Tombukt2

    Tombukt2 Senior Member

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    Yep that's pretty common.