Car not starting in key slot

Discussion in 'Gen 2 Prius Technical Discussion' started by richard203, Nov 9, 2025 at 9:23 AM.

  1. richard203

    richard203 Member

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    2008 Prius car does not start when putting the key in the key slot or keyless start. The only way it can start is putting the key under the steering wheel. This all started when the car died and have to jump started
     
  2. Tombukt2

    Tombukt2 Senior Member

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    That's interesting because the amplifier and antenna are built into the key slot I believe . The label on the bottom of the key slot denotes amplifier and a part number so now you're key under wheel . Nothing really down they're . I'd literally have to take my fob scanner and run it around the steer wheels amplifier etc and see what's pushing a signal . Really strange . I'm not sure how many antennae there are . And nothing's happened to fob . You only have 1?
     
  3. bisco

    bisco cookie crumbler

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    very strange. i would replace the fob battery with a new duracell, and get a free load test on the 12 volt at most auto parts stores.
    do you have a second fob?
     
  4. Brian1954

    Brian1954 Senior Member

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    Is this the same car that you created a thread about on October 16th? https://priuschat.com/index.php?posts/3572243
     
  5. richard203

    richard203 Member

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  6. Brian1954

    Brian1954 Senior Member

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    Have you charged the 12v battery completely (12 to 18 hours) yet?
     
  7. richard203

    richard203 Member

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    Yes we jumped and we drove it to charge up the battery and it starts up every-time without jumping it.
     
  8. Brian1954

    Brian1954 Senior Member

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    Did the same key previously work when you put it into the slot? Maybe the chip is missing inside the fob.
     
  9. richard203

    richard203 Member

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    the key works without putting it in the slot when it jump started and went for a drive and then when i turn it off it don't work no more. I tried with my second key and doing the same thing.
     
  10. Brian1954

    Brian1954 Senior Member

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    In post #7 you wrote:
    So now I am realy confused. FYI, for the car to fully charge the 12v battery, the car would need to be in Ready for 16 to 20 hours.

    Use a volt meter and measure at the jump point under the hood. What voltage do you measure?
     
    #10 Brian1954, Nov 9, 2025 at 5:57 PM
    Last edited: Nov 9, 2025 at 6:06 PM
  11. richard203

    richard203 Member

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    alright i'll measure the voltage when i get off work later. so if you drive the car for awhile like 2 hr the 12v battery wont be fully charged?
     
  12. Tombukt2

    Tombukt2 Senior Member

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    It would take longer than you have to drive charge a flat 12v forget it. You need an outlet and a battery charger preferably 8 amp .
     
  13. Brian1954

    Brian1954 Senior Member

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    No, it will not be fully charged because it had a very low charge when you started charging it. The car only charges the 12v battery at a low rate.