Weird battery readings on Dr Prius

Discussion in 'Prius v Technical Discussion' started by Camper V, Jun 5, 2026 at 6:53 PM.

  1. Camper V

    Camper V New Member

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    Location:
    Massachusetts
    Vehicle:
    2012 Prius v wagon
    Model:
    Two
    Hi Folks,
    Our 2012 V (83k) was doing just fine. Then we parked it for 4 months, and came back to the dreaded p0a80. Seemed suspicious. But we had a graduation party to go to so drove 700 miles; got 40.7 mpg with no issues. Got quotes from Green Bean and a few others but decided to take the battery out and have a look. The sensor wiring was badly corroded, so I replaced it and the bus bars, cleaned everything up, etc. On the bench all the cells were within .03 of each other, so that seems good.

    I put it back in and downloaded Dr Prius. Unfortunately I didn't know about this before removing the battery, so don't have comparison data. Here's what it shows:
    upload_2026-6-5_18-49-5.png

    I am virtually certain that I did not confuse any wires- I bought a good quality harness where the lengths are all correct and it really was not ambiguous as to which go where. And even if I had confused two of them, this oddness is before the crossover point from the sensors being on the positive, vs negative. Also, my wife just drove the car 80 miles and it ran perfectly normally, even though there are warning lights all over the dashboard...

    Well.... Any thoughts? And if we do need a new battery, are some of these companies more reputable than others?

    Thank you!
    Paul
     

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  2. rjparker

    rjparker Tu Humilde Sirviente

    Joined:
    Jun 6, 2008
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    Location:
    Texas Hill Country
    Vehicle:
    2012 Prius v wagon
    Model:
    Three
    It appears voltage sensor #8 is not connected or connected to the wrong place. Number 8's 16 volts is divided equally by sensors 7 and 9.

    Has to be a wiring problem of some kind on the sensors since the pack voltage at 231 vdc is reflecting all 14 modules.
     
    Brian1954 likes this.