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Triangle of death and other lights

Discussion in 'Gen 2 Prius Technical Discussion' started by carlos alfaro, Jul 19, 2023.

  1. carlos alfaro

    carlos alfaro New Member

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    Hello e everyone new here. I been working on cars not a living but hobby since 15 years old now 42. So I took on my coworker car as a small project. 2005 Prius the basic one gen 2. Well the triangle and other lights came on. I haven’t scan anything but I figured I know what it is. So just wanted some pointers were to start. I got the car for $600 bucks. Its runs great body is super straight clean title. Only thing I done is check the 12v battery through the car which reads at exactly 12v then I turn the headlights on and reads 11.6 then if I turn on the car it jumps to 14 or over. I had a Prius before and when my 12v battery was going bad it cause all those lights as well wondering if I’m having the same issue here. I did a quick test and had the car charged the big battery and then full matted to about 40mph and it only drop 2 bars so I don’t think my battery pack is bad? Also notice both my headlights would work then one would turn off
     
    #1 carlos alfaro, Jul 19, 2023
  2. mr_guy_mann

    mr_guy_mann Senior Member

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    Hello and welcome to PriusChat!

    So, there literally hundreds of possible faults that can trigger the "master warning" icon (Red Triangle of Death). Most of them will set diagnostic trouble codes in several of the 15 or 16 ecu's (computer control modules) that are in a Gen2 Prius.

    A very weak 12V battery can cause problems, but it has to be very weak, and I don't expect it to result in hybrid drive system fault codes. (maybe possible, but REALLY unlikely).

    Assuming that the car has good fluid levels for engine oil and coolant (both engine and inverter systems), then you need to scan ALL systems in the car to retrieve those codes. Most generic scantools - including most used by auto parts stores - can't communicate with all (or even most) systems in your Prius. I would hope that any decent auto repair shop is equipped with a capable scantool, but that's not a guarantee.

    One option is to read this thread that reviews several scantool apps and devices. Some are capable of scanning all systems on your car. Post #37 is a summary. (the Autel AP200 is a pretty good choice for many).

    FYI, your first five posts are moderated.
     
    #2 mr_guy_mann, Jul 21, 2023
  3. carlos alfaro

    carlos alfaro New Member

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    2005 Prius
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    One
    I have a ok scanner and I guess my inverter pump is not good anymore. So I order that and some coolant. I will flush the system just to be safe. But thanks for the reply
     
    #3 carlos alfaro, Jul 22, 2023
  4. mr_guy_mann

    mr_guy_mann Senior Member

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    What codes did you get? Do you have coolant circulating in the inverter tank with the car powered ON?

    As long as your scantool can check all 14-16 systems on a Gen2 Prius for codes and data then that's fine.

    (oops, forgot the link above)

    https://priuschat.com/index.php?posts/3290690

    Posted via the PriusChat mobile app.
     
    #4 mr_guy_mann, Jul 22, 2023
  5. carlos alfaro

    carlos alfaro New Member

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    2005 Prius
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    One
    P0a93 is the code I got and yea I check the pump fluid tank while running and sure enough it’s not circulating. Now I was looking at videos and it seems that best way to take it off is by taking the headlight out? That seem to be the most room available and easy to do
     
    #5 carlos alfaro, Jul 22, 2023
  6. ChapmanF

    ChapmanF Senior Member

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    I've never done it any other way.
     
    #6 ChapmanF, Jul 23, 2023
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