Error u0100 with Check Hybrid System

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by A.J, Jul 22, 2025 at 11:35 AM.

  1. A.J

    A.J Junior Member

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    Vehicle was parked outdoor for a month, rain fell during this period.
    HV battery has always had p0A80 error but do start and work normally. Error u0100 is new and won't let the vehicle start but kept showing Check Hybrid system.
    My scanner shows the u0100 error in 3 places:
    -ECU: 7EA
    -ECU: Hybrid engine system
    -ECU: Climate/Heater

    All error codes can be found in the attached PDF.
    I have reconditioned the HV battery thinking it was the issue, and Dr Prius reads the voltage properly with no issue.
    Any help will be appreciated.
     

    Attached Files:

  2. A.J

    A.J Junior Member

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    I also want to add that even with the triangle warning, the Hybrid engine drives the vehicle so far the battery is charged. But never moves over to the combustion engine. Which i guess whatever the issue is, it has to do with what kick starts the combustion engine. Because even in maintenance mode, error persist and combustion engine doesn't come on
     
  3. bisco

    bisco cookie crumbler

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    don't keep trying to start it. if the hybrid battery discharges too low, you will have to buy a charger or have it towed.