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Malfunctioning ECM and blown fuses

Discussion in 'Prius v Care, Maintenance and Troubleshooting' started by coach4docs, Mar 10, 2015.

  1. coach4docs

    coach4docs Junior Member

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    First...I freely admit to being in way over my head but am hoping others can jump in with thoughts/opinions.

    A dealership is attempting to charge me several hundred dollars to replace blown fuses that they claim is a result of an overpowered attempt at charging a seemingly dead 12V battery. The interesting part is that after also replacing the air/fuel ratio sensor (which they initially claimed was the cause of a check engine light even after replacing the fuses) Toyota is telling them that the ECM should be replaced in order to extinguish the check engine indicator.

    My basic question...if the vehicle is under warranty...is it possible that a malfunctioning ECM led to the no start condition originally and may have contributed to the blown fuses and malfunctioning sensor?
     
  2. Eclipse1701d

    Eclipse1701d Prius Enthusiast

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    I could understand a malfunctioning ECU causing a no start condition. What I can't understand is how the malfunctioning ECU produced enough current to blow the fuses. It sounds like what happens when an attempt is made to jump the vehicle with the positive and negative cables reversed. If that is the case, a few hundred dollars is pittance compared to what others have spent after that mistake.

    Did you or someone try to jump the vehicle?
     
  3. coach4docs

    coach4docs Junior Member

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    AAA came out to attempt a start with a battery pack. It appeared to me that the red handle was attached to the positive tab and the black to the frame. Would it matter if the sequence of connection was incorrect? Thanks
     
    Ulysses12 likes this.
  4. rdgrimes

    rdgrimes Senior Member

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    Food for thought: If the dealer is swearing that a faulty jump damaged the car, isn't the AAA service responsible for the damage?

    I'm the first to suggest the dealer service people are clueless, but if they put in writing.......

    Hard telling what the "jump pack" was actually delivering for voltage and current.
     
  5. Eclipse1701d

    Eclipse1701d Prius Enthusiast

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    It they were reversed, it could cost thousands in blown ecu's. If he had the pack set to a high enough voltage, it could have resulted in blown fuses and ecu's.
     
  6. mikefocke

    mikefocke Prius v Three 2012, Avalon 2011

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    I recall maybe 15 years ago a AAA guy telling me they used 24 volts to jump car batteries. Why, because it worked when a 12 volt from my car to my dad's didn't.

    No idea if that was correct or if they still do it.

    AAA has a guide for their people for towing specific vehicles and I'd be surprised they don't have one if they have found the Prius needs special handling when jumping. Did they follow company policy?
     
  7. Mike500

    Mike500 Senior Member

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    On account of all the damage that can happen to the Prius ECU, I'll NEVER let anyone else but a Toyota dealer touch the battery.

    I carry one of these Antigravity lithium ion "jump packs."



    I'm considering wiring the pigtail directly to my 12 volt to make sure that the polarity is not reversed.
     
  8. Jtm3djad

    Jtm3djad Junior Member

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  9. Jtm3djad

    Jtm3djad Junior Member

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    I botched a jump by reversing the clamps. The car was totally dead after that, with the exception of a couple of lights on the dash. I replaced the fuseable link block, and everything works fine, so far, but there are several lights on that mean "take it to te dealer". I also repaced two fuses.. I'm wondering if those are on because of the car's having been dead, and the replacement. Is there a place/way to turn the lights off? Would a diagnostic from auto zone tell if those emergency lights are real indications of an issue, or have come on because of the block being changed? I have driven it on the street some andall appears to be okay; the brake light is on, but the fluid is not low or empty. I haven't tried slamming on the brakes, but wanted to get more info. Anyone know/ f? I hate paying big sums for them to handle it if the lights are just on, but not an indication of real issues. thanks.
     
  10. Joel Arevalo

    Joel Arevalo New Member

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    What fuses have you checked
     
  11. mr_guy_mann

    mr_guy_mann Senior Member

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    You do realize that you are responding to a post from 7 years ago?
     
  12. Air_Boss

    Air_Boss Senior Member

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    LOL. Just wondering if the fuses kept blowing...
     
  13. ChapmanF

    ChapmanF Senior Member

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    My Antigravity pack comes with "smart clamps" that detect the polarity, and won't conduct if you have them backwards.

    The first one I bought came with dumber clamps, but when Antigravity upgraded the model to come with the smart ones, they also made the smart clamps available separately, so I upgraded my old one.

    There is one possible thing to watch for: if your battery is so completely dead that the smart clamps can't tell if they're forwards or backwards, then you have to push an override button to make them conduct. So in that situation, you'd still better double-check your colors before pushing that button.

    I made a point of buying mine straight from Antigravity's web site, because there were reviews on Amazon from people who had ordered there and received packs that were unmistakably counterfeit. I wouldn't really be comfortable with a large-capacity, counterfeit Li-ion battery stored in my glove box.