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Bad wiring harness??

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Christopher Kim, Oct 28, 2023.

  1. Christopher Kim

    Christopher Kim Junior Member

    Joined:
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    North Carolina
    Vehicle:
    2004 Prius
    Model:
    Base
    Hey guys. I have a 2nd gen Prius. So I originally got a p3030 code earlier this month. Drove around and cleared the code. It was fine driving wise, popped up again a week later but I went ahead and ordered an ecu/wiring harness from eBay. The new part came in and I went ahead and installed both. Car started acting weird and even dr Prius app interface was super choppy. Eventually code p3012 which referenced block 2 was bad. Made no sense, so I went ahead and put my old one back on. Interface was much better and back to normal but now it’s referencing to p3017 which refers to block 7 but I never had this issue before. Could it be just my wiring harness that’s bad?? Or should I go ahead and replace that block?
    Also whenever I replaced my bus bar, I used the screws that came with it that has the ridges compared to the old nuts that was smooth. Could that cause damage?? Any help would be appreciated. Thanks
     
    #1 Christopher Kim, Oct 28, 2023
    Last edited: Oct 28, 2023
  2. Tombukt2

    Tombukt2 Senior Member

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    Location:
    Durham NC
    Vehicle:
    2009 Prius
    Model:
    Base
    Sounds like you're playing whack a mole with bad blocks of batteries usually that just goes on for a long time till you get broke busted and disgusted and wind up back in the gas car or spend real money and get a real battery that works but you don't have to worry about for say 7 plus years It just takes some people longer to get to that point or they throw their hands up and since the cars a generation too they might have got a little increase at work they can go get that big car loan they've always wanted so there's always that. Seems to me once things start going on with the HV battery and/or the 12 volt You're either heading to replace with a new or replaced with used and play the games especially with the HV battery sometimes you get lucky with a used rebuilt type battery and it can work for a while. In my personal car that I use for my business I just have a new Toyota battery that way there I can play around with all the other nonsense at least I know my HD battery my inverter and the charge motors are pretty much doing their jobs You can play around with inverter pumps and water control valves and so on and so forth but those other three items kind of need to be kept up.
     
  3. Christopher Kim

    Christopher Kim Junior Member

    Joined:
    Aug 14, 2023
    31
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    Location:
    North Carolina
    Vehicle:
    2004 Prius
    Model:
    Base
    I am saving up for a new battery. But in the mean time, I’m just trying to make this work. The p3030 reference a high voltage line snapped. So that could be my wiring harness correct? Like I said, I replaced it with a unit on eBay but I think it was bad. I never had any of these cell codes pop up before until I made the swap with the ecu and wiring harness. I’m only getting code p3017 but it’s weirdly reading with dr Prius. It’s either super high in reading or super low. Which makes the volt difference above .5 which throws the code.