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2012 Toyota Prius Check Engine Light keeps on popping up

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Ozyamandias77, Sep 28, 2022.

  1. Ozyamandias77

    Ozyamandias77 New Member

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    Hello all, so I have a 2012 Toyota Prius, and I took it 6 six weeks ago to get an oil change due to check engine light coming on and it was about that time. 2 weeks later (or 4 weeks ago), the check engine light comes on, and I take it to the mechanic for a quick oil change, because they put too little apparently. Just yesterday, a whole month ago after my second trip to the mechanic, the check engine pops on the dashboard again. The oil levels are okay, and my car works fine, so what would be the issue?
     
  2. tankyuong

    tankyuong Senior Member

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    scan the codes
     
  3. bisco

    bisco cookie crumbler

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    check engine does not mean check the oil. it's an emission issue. make sure the fuel cap is secure, and the gasket is good
     
  4. ChapmanF

    ChapmanF Senior Member

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    To elaborate just a little bit:

    There are a hundred or so different reasons that check-engine light can come on. When it does, the computer that turns it on also stores some diagnostic codes to say what the issue is.

    The car has a diagnostic port under the dash, and by plugging in an onboard-diagnostics scan tool, you can find out what the codes are. If you post those here, we can explain what's going on.
     
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  5. nicoj36

    nicoj36 Active Member

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    You can get an obd tool on Amazon and use the torque app or Dr-prius app to scan the check engine codes and find out what exactly the issue.
     
  6. Tombukt2

    Tombukt2 Senior Member

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    I think it's a maintenance required light that comes on reminding you that you need to deal with your oil change and maintenance check engine light comes on for completely different reasons letting you know that one of the many systems in this vehicle has seen something that is questionable to its parameters and it wants somebody to take a closer look because it can't do it by itself. So you need to get a human to do that closer looking thing..
     
  7. ChapmanF

    ChapmanF Senior Member

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    A Gen 3 Prius doesn't use a maintenance-required light as an oil change reminder. Instead, it shows a message "OIL MAINTENANCE REQUIRED" on the MID.
     
  8. bisco

    bisco cookie crumbler

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    i think mine just says 'maintenance reminder'
     
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  9. ASRDogman

    ASRDogman Senior Member

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    Are you sure it's the check engine light? Sounds like an oil issue.
    Another oil change in 2 week?????
    Are you sure it's not the OIL level light????? You could have a bad oil pressure switch.
    Maybe take a photo of it and post here.

    And you can ask the place that changed your oil what light it is....

     
  10. ChapmanF

    ChapmanF Senior Member

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    In my 2010 anyway, the messages from that reminder system are these:

    oilm.png

    It's easy to be sure it's not the oil level light, because there isn't one. And as for oil pressure, what you see for that in a Gen 3 is the master warning triangle plus a message on the MID:

    oilp.png

    Speaking of engine oil pressure warnings, it can't be repeated too often that no one should ever wait for them as some kind of signal for when to add oil. By the time the oil pressure is lost and this warning appears, the engine is already eating itself. It's vital to check the dipstick under the hood regularly, and proactively keep the oil level correct so that this warning is never, ever seen.
     
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  11. bisco

    bisco cookie crumbler

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    i have never seen any of those messages
     
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  12. Michael Wood

    Michael Wood Active Member

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    In my 2015 the 5000 mile oil change reminder only says "Maintenance Required". No mention of oil.
     
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  13. Tombukt2

    Tombukt2 Senior Member

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    I want to say that's what the 2013 does too maintenance required.
     
  14. ASRDogman

    ASRDogman Senior Member

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    That IS what the maintenance is...
     
  15. ChapmanF

    ChapmanF Senior Member

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    Maybe they changed the wording some time after 2010 because someone thought "oil maintenance" sounded funny.
     
  16. Mendel Leisk

    Mendel Leisk Senior Member

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    Canadian Prius owners (3rd gen at least) muddle through, without any maintenance messages.