1. Attachments are working again! Check out this thread for more details and to report any other bugs.

I am getting a P0AFA and P3000

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by chronon, Jul 12, 2019.

  1. chronon

    chronon Active Member

    Joined:
    Jun 14, 2007
    601
    106
    3
    Location:
    here and there aint be in frozen wasteland no mo..
    Vehicle:
    2005 Prius
    Model:
    ----USA----
    Without a techstream, is it possible to narrow this down to the ECU / modules ?
    For ref:
    P3000 – Toyota Prius Hybrid Fault Code Diagnosis
    P3000 – Battery Control System
    The P3000 fault code relates to the battery control system in the Toyota Prius. If this code is displaying on your vehicle, it means that there is a problem with the HV battery ECU. The problem can be caused by several different sources, making P3000 a very generic and common fault code.

    The P3000 fault code will often be accompanied with a suffix (for example, P3000-388) to help with diagnosing the source of this problem. The definition of these suffixes (or INF codes) can be found below:

    P3000-123
    Abnormal signal response from the battery ECU, often associated with a high-voltage battery system malfunction.
    Possible causes include: HV battery system, Battery ECU

    P3000-124
    Abnormal signal response from the battery ECU, commonly associated with a blown fuse.
    Possible causes include: HV battery system, Battery ECU

    P3000-388
    Discharge Inhibition Control Malfunction. This code is triggered when the battery’s state of charge decreases due to the vehicle being left in N position, running low on fuel or a malfunction occurring in the HV control system.
    Possible causes include: HV control system, HV battery assembly or a fuel shortage

    P3000-389
    Drop of battery voltage detected by the battery ECU. This code is output if the HV battery is depleted or the battery control system malfunctions.
    Possible causes include: HV control system, HV battery assembly

    P0AFA Toyota Hybrid Battery System Voltage Low
    P0AFA Toyota Hybrid Battery System Voltage Low

    OBD Code:
    System:
    Subsystem:
    P0AFA Toyota – (ASE)
    Powertrain

    Trouble Code Description: Hybrid Battery System Voltage Low
    Hybrid Battery Pack ground cable or connection What does this mean? Possible symptoms Engine Light ON (or Service Engine Soon Warning Light) P0afa Description The Engine Control Module (ECM) monitors the correlation of the generator battery disconnect control module battery voltage and the Starter Generator Control Module (SGCM) output voltage to detect a 36 volt cable open or fuse/relay failure. The ECM also monitors to detect a+n over voltage condition and protect the MOSFET (load dump). If either one of these conditions is detected, the appropriate Diagnostic Trouble Code (DTC) will set.


     
  2. SFO

    SFO Senior Member

    Joined:
    Feb 7, 2017
    5,302
    4,241
    0
    Location:
    Northern California
    Vehicle:
    2007 Prius
    Model:
    N/A
    Not really, but torque may be able to get you closer if you look at the static block voltages, and again while accelerating and braking

    Give the thrown DTCs, you should do a visual inspection of the HV battery ECU and associated orange connector for corrosion. If you find nothing there, then continue into the HV battery and look for corrosion on the voltage sensing wires that attach to each module.

    [​IMG]
     
    Raytheeagle likes this.
  3. fragglestickcar

    Joined:
    Apr 4, 2018
    77
    41
    0
    Location:
    New York
    Vehicle:
    2006 Prius
    Model:
    II
    My orange connector looked like above (second pin from edge broke off), and replacing the ecu fixed the problem.