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What should I do with my 2009 that died? DTC codes P0A94 P0A80 P010A

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by rodo111, Jul 18, 2019.

  1. rodo111

    rodo111 New Member

    Joined:
    Jul 18, 2019
    2
    0
    0
    Location:
    Tempe, AZ
    Vehicle:
    2009 Prius
    Model:
    II
    Some background:

    2009 Prius Gen II Base, 177k miles which I know isn't necessarily a lot for this car. It has been burning oil more quickly lately, though, and I never really got great gas mileage from it (~40mpg). I bought it used at around 55k miles.

    Recently I have been having more of the intermittent combo meter issues where the dash turns off, and I have been resetting it by unplugging the 12V battery for a few seconds and plugging it back in. It was happening often lately so I made the very stupid mistake of not properly covering the battery terminals when I was last driving this car (they were exposed in the trunk). More on this later.

    I had not seen any check engine or anything like that regarding the hybrid battery recently, car was driving okay with more frequent oil changes and topping off if necessary.

    What happened:

    I was driving and (luckily) close to home when I made a turn and the car suddenly jerked and all the dash lights came on, including red triangle of death. Acceleration was very slow and eventually wouldn't go anymore. I was able to restart the car a couple times and got it to drive for a few seconds at a time before it once again stalled. Right now it's sitting in front of my house.

    Now about that 12V battery...I had a pair of scissors in my trunk and I found it lodged in the battery cavity in the trunk, which was, as I mentioned, very stupidly exposed. There is no corrosion or anything on the scissors, but I think it is possible this shorted the battery terminals. This may have blown a fuse or "reverse jumped" the car while it was driving, which could be an inverter issue or not (not sure). I tried checking the fuses with my multimeter and they all seemed to be good as far as I could tell, but it's possible I did something wrong.

    Screenshot of some random android app with my wifi OBDII reader is attached, the codes are P0A94 (x2), P0A80, P010A. I assume the P0A94 has some sub codes that I will try to read with a different app.

    Several theories:
    - bad fuses (checked but not sure if I did it correctly)
    - blown inverter (this would suck)
    - bad hybrid battery, though I have not had any warnings about it before it suddenly went out

    Additionally, the 12V battery seemed to be leaking or corroded a bit, and it's probably less than 2 years old (optima yellowtop), so is it possible that just replacing the 12V battery would fix my issue? The car still turns on and I can operate everything, but it won't drive, so I'm not certain this is the only problem.

    I decided I do not want to keep trusting this car to get me around and take long drives across the desert (which I do fairly often), so I've already moved on to a different vehicle. However, I am trying to figure out what's wrong with my prius. If the cost is reasonable to fix it, the car probably still has a lot of life left and can be of use to someone. The only real issues besides this electrical stuff are the combo meter issues (which can probably be a DIY fix) and the oil consumption. My choices are either to get it repaired and try to sell it (which would involve diagnosing the issue) or to just call a junkyard to haul it away. I might part out a few easy things, but honestly I don't have a ton of time to do that.

    Any ideas?
     

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  2. rodo111

    rodo111 New Member

    Joined:
    Jul 18, 2019
    2
    0
    0
    Location:
    Tempe, AZ
    Vehicle:
    2009 Prius
    Model:
    II
    I should also mention the following facts:
    • This was in summer in Arizona (end of June, so it's hot outside)
    • Recently my smart key fob was not working either (I assumed due to battery which I had not yet replaced in the fob), but it would work fine if I inserted the key fob into the slot.
    Not sure if that information is relevant, but I am putting it out there.
     
  3. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,200
    6,475
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    Can you make the Prius READY? If you can, do so and measure voltage across the 12V battery. If you get a reading much lower than 13.8V, the DC/DC converter is not working, which is the meaning of P0A94. As you mentioned, having the three digit subcode might provide more granular information. Should you find the DC/DC converter is not working, check the DC/DC fusible link which is located in the 5" white/clear plastic box located in the main relay/fuse box next to the inverter.

    You probably know that P0A80 points to a high voltage traction battery failure.

    Regarding P010A, try removing and cleaning the mass air flow sensor.