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2012 Prius Check Hybrid System Codes

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by flatcappedmadman, Apr 10, 2023.

  1. flatcappedmadman

    flatcappedmadman New Member

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    Apr 10, 2023
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    Location:
    Bear, New Castle, Delaware, USA
    Vehicle:
    2012 Prius
    Model:
    Two
    Was out driving today and the "Check Hybrid System" notification came on. I got it to an Advanced Auto to check the codes. The codes were:


    p0a80 - hybrid battery
    c1241 - low power supply voltage malfunction
    c1252 - brake booster pump motor ON Time Abnormally Long
    c1256 - accumulator low pressure

    I didn't notice any difference in the way it drives. It's not making any random sounds. I haven't really noticed any difference with the brakes, but I'm pretty easy on the brakes anyway.

    Any ideas what could be the issue and a general idea what the cost to fix it might be?
     
    #1 flatcappedmadman, Apr 10, 2023
  2. bisco

    bisco cookie crumbler

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    Plug-in Base
    i think it unlikely the battery and brakes went simultaneously. i would check the 12 volt health and get a scan from tech stream.
     
    #2 bisco, Apr 10, 2023
    flatcappedmadman likes this.
  3. taxidriver50005

    taxidriver50005 Active Member

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    Model:
    Excel
    Sounds like hybrid battery fault, low voltage will bring up the other codes too

    Posted via the PriusChat mobile app.
     
    #3 taxidriver50005, Apr 11, 2023
  4. ChapmanF

    ChapmanF Senior Member

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    Vehicle:
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    IV
    The C1241 tells you that inadequate electrical power was arriving at the brake system. Sometimes that's a problem with the 12 volt battery, sometimes it's something else on the way from there to the brake system where the power was measured. So some troubleshooting needs to be done; the C1241 section in the repair manual will suggest how.

    Toyota Service Information and Where To Find It | PriusChat

    With inadequate power arriving at the brake system, it might be hard for the pressure pump to build up pressure, and as a result the pressure might be low, so don't panic about the C1252 and C1256 unless you still get them after fixing whatever's causing the C1241.

    There's no causal relationship in either direction between those things and the P0A80. That's just another thing.
     
    #4 ChapmanF, Apr 11, 2023
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