2008 won't power on....no lights no nothing!

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by bithead2, May 23, 2025 at 7:29 PM.

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  1. bithead2

    bithead2 Junior Member

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    I have a 2005 and a 2008. I moved the 2005 into the garage and started taking the engine out to do a swap.

    And literally the same day I did that the 2008 refused to start!

    I charged up the 12V battery and so it isn't that. I also tried jumping it under the hood. When I put the key fob in or press the Start button literally nothing happens.

    I can't figure out what changed. Maybe when I washed the engine with a sprayer? It did run enough to park after that. But who knows?

    I asked Grok AI for some tips and got some astoundingly obvious stuff that definitely isn't the problem. What is the most common cause of this in Gen 2? The 12V battery should at LEAST turn the dash lights on and it isn't even doing that.

    Thanks, CJ
     
    #1 bithead2, May 23, 2025 at 7:29 PM
  2. Tombukt2

    Tombukt2 Senior Member

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    Well that's a good place to start you should be able to turn the lights on without doing anything else the flashers etc till we have at least that going on you have no vehicle so we're starting at the 12 volt back in the right rear sounds like it's going to need to be replaced probably because well probably been in there a while and being as you have two cars things get swapped and messed with and anyway get to 12 volt sorted out directly and then you can go from there magically that's the key to most everything and this model Prius is a faulty 12 volt
     
    #2 Tombukt2, May 23, 2025 at 7:48 PM
  3. Brian1954

    Brian1954 Senior Member

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    Use a meter to measure the voltage of the 12v battery.
     
    #3 Brian1954, May 23, 2025 at 9:44 PM
  4. JC91006

    JC91006 Senior Member

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    Maybe check your 12v connections, make sure the ground is tightly bolted to the body of the car.
     
    #4 JC91006, May 23, 2025 at 10:00 PM
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  5. mr_guy_mann

    mr_guy_mann Senior Member

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    Do the headlights work? Do the brake lights work? If the answer to both questions is yes, then check the AM2 fuse in the underhood fuse box.

    A not uncommon fault is that the inverter coolant pump shorts and pops the fuse. Without that power feed, the car cannot turn on.

    Posted via the PriusChat mobile app.
     
    #5 mr_guy_mann, May 23, 2025 at 10:42 PM
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