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Red Triangle after 12v battery replacement

Discussion in 'Generation 1 Prius Discussion' started by Anna Payesko, Oct 4, 2024.

  1. Anna Payesko

    Anna Payesko New Member

    Joined:
    Sep 1, 2024
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    Location:
    Big Island
    Vehicle:
    2001 Prius
    Model:
    N/A
    I just got my 01 prius back after a month of not driving it. I lost all my keys and had to get the ecu replaced at the dealership and they replaced my 12v as well because apparently the one the previous owner had in the car was aftermarket. I just got the car back three days ago and its been driving totally fine since then but the red triangle came on when I was driving home this morning. I pulled over and checked under the hood and checked under the car but nothing looked seriously wrong and I didn’t notice anything wrong with the way it was driving. It was only less then a mile back to my house so I just drove it home carefully, nothing seemed wrong with it on the drive back. Called the dealership and they said they would read the codes and fix it if it was an issue with the battery but when I went to take the car in the warning light had gone away. It had been about 3 hours since it came on at this point. Is this likely an issue with the battery or could it be something thats come up with the car sitting so long? I dont think its the hybrid battery because the one in this car was replaced before i bought it, though i dont know at what mileage. Ive been paying attention to the hybrid battery display the past few days and it seems to be acting normal. Should I keep driving the car until the triangle comes back on and they can read the codes? Any ideas on what the issue could be?
     
    #1 Anna Payesko, Oct 4, 2024
  2. Tombukt2

    Tombukt2 Senior Member

    Joined:
    Nov 29, 2020
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    Location:
    Durham NC
    Vehicle:
    2009 Prius
    Model:
    Base
    Keep driving the car maybe find yourself a cheap scanner that you can keep with you so you're not worrying with the dealership and foolishness to be honest with you it sounds like you may have the hybrid isolation fault which if you have a voltmeter that reads DC volts you can measure between the bottom bolt that holds the fuse in the hybrid safety plug and the frame of the car and the voltmeter should count down to zero DC volts not 40 not 60 not 35 but zero If any other number is displayed you have battery voltage leaking to the frame of the car which is the grounding point for your 12 volt battery not an ideal situation and can make the triangle come on usually when this happens the car won't restart till you clear the code so it may not be that or it may be very intermittent it's worth a check given the fact you don't know when the hybrid battery was replaced you don't know with what a brand new hybrid battery doubtful this is one thing that people don't like to spend money on and don't want to hear about a 2000 plus dollar battery so it is one of the last things that gets dealt with or it gets patched with Band-Aids rather than truly fixed or replaced It's worth a check it's a long shot a code reader is a good thing for you to have and one of the best $80 things you will buy for your car I would certainly be looking to get one an AP200 which is been discontinued is a nice little tool for your car and it's relatively inexpensive as scanners and things like this go it would be a very wise purchase
     
    #2 Tombukt2, Oct 5, 2024
  3. ronlewis

    ronlewis Active Member

    Joined:
    Dec 5, 2016
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    Location:
    texas
    Vehicle:
    2001 Prius
    Model:
    One
    Take it to the dealer to have it scanned for codes. Sounds like it won't have any now, but they might be able to see the ones that cleared.

    Can't even imagine what they charged you for the ECU and key. I got a locksmith to just reprogram mine for a couple hundred bucks, but I pulled it out myself and put it back in. Not hard to do really, just a few screws and a bolt, but it is behind the dash and it helps to have small hands.

    And replacing a 12v because it's aftermarket is a waste. All I use are aftermarket batteries.
     
    #3 ronlewis, Oct 5, 2024
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