My car has need a boost for 7 straight days

Discussion in 'Gen 5 Prius Technical Discussion' started by Paul Gregory, Aug 24, 2025 at 12:38 PM.

  1. Paul Gregory

    Paul Gregory Senior Member

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    But I'm not blaming this one on wireless updates. I'm running an electric cooler, and my NOCO Genius 5 wasn't working, so I went out and bought a new one. Turns out it's a faulty connection in the fusebox. No continuity through the 10 mil lug it's attached to. I just need to clean it up and reconnect.

    I need to return the new one.

    UPDATE: It was a blown fuse. Why would they use a 4A fuse on a 5A charger? It has a 5 amp fuse now.
    I think I'll keep the new one; it was on sale, and it will be good to have a spare, which I'll probably need some day.
     
    #1 Paul Gregory, Aug 24, 2025 at 12:38 PM
    Last edited: Aug 24, 2025 at 2:44 PM
  2. bisco

    bisco cookie crumbler

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    phew, i thought we were back to the 12 volt issue when i saw the title. glad it is unrelated to vehicle issues
     
  3. rjparker

    rjparker Tu Humilde Sirviente

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    Same issue and it's not the car
     
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  4. Brian1954

    Brian1954 Senior Member

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    Did you ever own a NOCO Genius 2 amp charger? Maybe you are using the wire harness from it with the NOCO Genius 5 amp charger.

    What you posted got me thinking about the three different size NOCO chargers that I own. So I took a look at them.
    The NOCO Genius 1 amp charger uses a 2 amp fuse in the wire harness.
    The NOCO Genius 2 amp charger uses a 4 amp fuse in the wire harness.
    The NOCO Genius 5 amp charger uses a 10 amp fuse in the wire harness.
     
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  5. Paul Gregory

    Paul Gregory Senior Member

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    You may be right. I can't recall where the fuse was located. I did simply plug the new charger into the existing wiring. I had originally started with a NOCO Genius 2 and upgraded to a 5.

    UPDATE: You are correct. I just confirmed that the 4A fuse was in the part of the wiring harness that came with my Genius 2, which I left in place when I upgraded to the Genius 5. Nice catch.
     
    #5 Paul Gregory, Aug 24, 2025 at 11:24 PM
    Last edited: Aug 24, 2025 at 11:58 PM
  6. Mendel Leisk

    Mendel Leisk MMX GEN III

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    Good plan, I do my share of that too.
     
  7. Paul Gregory

    Paul Gregory Senior Member

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    I've tried other battery maintainers, usually cheaper to buy, but disappointing to use. The damned thing was turned off, letting the battery go dead. The NOCO is always working when you need it to.
     
  8. bisco

    bisco cookie crumbler

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    i have the little noco .75 amp maintainer fo 30 bucks. it does a great job while we're away for 3 months every winter.
     
  9. Paul Gregory

    Paul Gregory Senior Member

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    I upgraded from 2 amps to 5 amps because my drinks cooler was drawing nearly 5 amps.
     
  10. bisco

    bisco cookie crumbler

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    good reason. my car is stock, i have no idea what the draw is when off, but it most be lower than .75
     
  11. Gokhan

    Gokhan Senior Member

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    I said this in another thread:
    So, now, we know. The car has practically stopped recharging the 12-V battery and it drains overnight every night unless you hook up a battery maintainer every night.

    I doubt you can remedy the situation by readjusting the battery-isolator voltages. It looks like either the primary battery or the auxiliary battery drains depending on the voltages.

    The battery draining every night unless you connect a battery maintainer is something nobody wants. The easiest solution is to get rid of the auxiliary battery and the battery isolator, but to each his own.
     
  12. Mendel Leisk

    Mendel Leisk MMX GEN III

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    Drink your beverages at room temp?
     
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  13. Paul Gregory

    Paul Gregory Senior Member

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    I only keep the drinks cooler running 24/7 in the summer.