Scangauge 2 4.52 killing Gen 5 12v Battery?

Discussion in 'Gen 5 Prius Care, Maintenance and Troubleshooting' started by DOHCtor, May 14, 2025.

  1. DOHCtor

    DOHCtor Member

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    Anyone knows why my Scangauge 2 is killing my Gen 5 battery? It used to work flawlessly in my 2021 Prime but now, it seems like it's useless in my 2024 Prime. I've set it in hybrid mode. Would have wanted to use it to monitor various temps and RPM..

    TIA!
     
    #1 DOHCtor, May 14, 2025
  2. Trollbait

    Trollbait It's a D&D thing

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    Have you checked to see if there are more recent firmware updates available?
    I suggest contacting Linear Logic, they have had great customer support in the past.
     
    #2 Trollbait, May 15, 2025
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  3. DOHCtor

    DOHCtor Member

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    Yep! Had an answer.

    Is your 2024 Prius Prime plugged into the charger?
    The ScanGauge unit will wake up when a plug in hybrid vehicle is being charged. The ScanGauge reads the rise in battery voltage thus causing the ScanGauge to wake up. This is normal. Unfortunately there is no way to turn this off other then to unplug the ScanGauge unit while the vehicle is being charged.

    Weird thing is, my 2021 Prime wasn't doing this.. anyway. Guess we have an answer.
     
    #3 DOHCtor, May 15, 2025
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  4. DOHCtor

    DOHCtor Member

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    Hmmmm.... it certainly wasn't pluggen in at work but the scangauge is wide awake... looks like it's a no no on a 5th gen...

    20250516_104059.jpg
     
    #4 DOHCtor, May 16, 2025
  5. otatrant

    otatrant Active Member

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    One way I have found around 12V battery drain when charging leaving the car in room mode. You have to lock your car with the physical key at the drivers door and if you don't want your climate control running you need to turn it off and same with the infotainment screen and automatic headlights.
     
    #5 otatrant, May 20, 2025
  6. ChapmanF

    ChapmanF Senior Member

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    In that case it seems there is another issue besides the known one about charging, and it would be worth contacting Linear Logic again. Like Trollbait, I have heard good things about their customer service.
     
    #6 ChapmanF, May 20, 2025
  7. Trollbait

    Trollbait It's a D&D thing

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    It was personal experience on my end. They did a firmware update when my scangauge was causing errors in the Sonic, then replaced the screen when I dropped it. Was only the cost to ship it to them for me.
     
    #7 Trollbait, May 20, 2025
  8. douglasjre

    douglasjre Senior Member

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    Where is it made?
     
    #8 douglasjre, Jun 9, 2025
  9. ChapmanF

    ChapmanF Senior Member

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    The ScanGauge? Linear-Logic's contact address is in Mesa, Arizona, with a 480 telephone area code.

    Who knows where their manufacturing happens.
     
    #9 ChapmanF, Jun 9, 2025
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  10. Trollbait

    Trollbait It's a D&D thing

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    Amazon listing for the Scangauge III lists USA for origin.
     
    #10 Trollbait, Jun 9, 2025
  11. mountaineer

    mountaineer Active Member

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    I documented my problems with the ScanGauge II here when I got my 2023 Gen 5 Prius Prime.

    I disconnected it and haven't plugged it back in, because once I did and forgot to unplug it and drained my 12V again :(

    Have had continuing issues with my 12V...
     
    #11 mountaineer, Jun 29, 2025
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