HYBRID CONTROL SYSTEM, Diagnostic DTC:P31B300

DTC Code DTC Name
P31B300 Hybrid/EV Battery Voltage High

DTC SUMMARY


  1. MALFUNCTION DESCRIPTION

    The hybrid vehicle control ECU assembly uses the inverter voltage to monitor the HV battery voltage and detect malfunctions.

    The cause of this malfunction may be the following:


      Inverter with converter assembly malfunction (Boost converter system)

    • VL sensor malfunction

    • VH sensor malfunction


      HV battery system

    • Battery ECU assembly malfunction

    • HV battery malfunction

DESCRIPTION

The hybrid vehicle control ECU assembly uses the inverter voltage to monitor the HV battery voltage and detect malfunctions.

DTC No. Detection Item DTC Detection Condition Trouble Area MIL Warning Indicate
P31B300 Hybrid/EV Battery Voltage High

The inverter voltage exceeds the threshold.

(1 trip detection logic)

  • Inverter with converter assembly

  • Battery ECU assembly

  • No. 1 HV supply stack sub-assembly

  • No. 2 HV supply stack sub-assembly

 Comes on

Master Warning Light:

Comes on
Related Data List
DTC No. Data List
P31B300 -

CONFIRMATION DRIVING PATTERN

Tech Tips

After repair has been completed, clear the DTC and then check that the vehicle has returned to normal by performing the following All Readiness check procedure.

Click here


  1. Connect the GTS to the DLC3.

  2. Turn the power switch on (IG) and turn the GTS on.

  3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).

  4. Turn the power switch off and wait for 2 minutes or more.

  5. Turn the power switch on (IG) and turn the GTS on.

  6. Turn the power switch on (READY) and wait for 30 seconds or more.

  7. Enter the following menus: Powertrain / Hybrid Control / Utility / All Readiness.

  8. Check the DTC judgment result.

    Tech Tips


    • If the judgment result shows NORMAL, the system is normal.

    • If the judgment result shows ABNORMAL, the system has a malfunction.

    • If the judgment result shows INCOMPLETE, perform driving pattern again.

CAUTION / NOTICE / HINT

CAUTION:


  • B004STG

    Before the following operations are conducted, take precautions to prevent electric shock by turning the power switch off, wearing insulated gloves, and removing the service plug grip from HV battery.


    • Inspecting the high-voltage system

    • Disconnecting the low voltage connector of the inverter with converter assembly

    • Disconnecting the low voltage connector of the HV battery

  • B004Y5N

    To prevent electric shock, make sure to remove the service plug grip to cut off the high voltage circuit before servicing the vehicle.

  • B004SX1

    After removing the service plug grip from the HV battery, put it in your pocket to prevent other technicians from accidentally reconnecting it while you are working on the high-voltage system.

  • B004W3JC06
    *a Without waiting for 10 minutes

    After removing the service plug grip, wait for at least 10 minutes before touching any of the high-voltage connectors or terminals. After waiting for 10 minutes, check the voltage at the terminals in the inspection point in the inverter with converter assembly. The voltage should be 0 V before beginning work.

    Click here

    Tech Tips

    Waiting for at least 10 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.

  • Make sure to insulate the high-voltage connectors and terminals of the HV battery with insulating tape after removing it.

    If the HV battery stored without insulating the connectors and terminals, electric shock or fire may result.

  • B004SCIC04
    *a Dealer
    *b Battery Collection Agent

    When disposing of an HV battery, make sure to return it through an authorized collection agent who is capable of handling it safely. If the HV battery is returned via the manufacturer specified route, it will be returned properly and in a safe manner by an authorized collection agent.


    • Accidents such as electric shock may result if the HV battery or the HV supply stack sub-assembly is disposed of improperly or abandoned.

      Therefore, make sure to return HV battery and all HV supply stack sub-assemblies through an authorized collection agent.

  • Before returning the HV battery, make sure to perform a recovery inspection.

    Click here

  • Before returning the hybrid vehicle supply stack sub-assembly, make sure to perform a recovery inspection.

    Click here

  • Make a note of the output DTCs as some of them may be necessary for recovery inspection of the HV battery and hybrid vehicle supply stack sub-assemblies.

  • B004X4P

    After removing the HV battery or the HV supply stack sub-assembly, keep it away from water. Exposure to water may cause the HV battery or the HV supply stack sub-assembly to produce heat, resulting in a fire.

Note

After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work.

Click here

WIRING DIAGRAM

Refer to the wiring diagram for the HV battery high-voltage line circuit.

Click here

PROCEDURE


  1. CHECK DTC OUTPUT (HYBRID CONTROL, MOTOR GENERATOR)


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Enter the following menus: Powertrain / Hybrid Control and Motor Generator / Trouble Codes.

    4. Check for DTCs.


      Powertrain > Hybrid Control > Trouble Codes
      Powertrain > Motor Generator > Trouble Codes
      Result
      Result Proceed to
      P31B300 only is output, or DTCs except the ones in the table below are also output. A
      DTCs of hybrid control system in the tables below are output. B
      DTCs of motor generator control system in the tables below are output. C
      Malfunction Content System Relevant DTC
      Sensor and actuator circuit malfunction Hybrid control system P0D2D1C Drive Motor "A" Inverter Voltage Sensor Voltage Out of Range
      P0E311C Boosting Converter Voltage Sensor "A" Voltage Out of Range
      P1C2D62 Hybrid/EV Battery "A" Voltage Sensor/Boosting Converter Voltage Sensor "A" Signal Compare Failure
      Motor generator control system P0D2D16 Drive Motor "A" Inverter Voltage Sensor (VH) Circuit Voltage Below Threshold
      P0D2D17 Drive Motor "A" Inverter Voltage Sensor (VH) Circuit Voltage Above Threshold
      P0D2D1F Drive Motor "A" Inverter Voltage Sensor(VH) Circuit Intermittent
      P0E3116 DC/DC Converter Voltage Sensor "A" (VL) Circuit Voltage Below Threshold
      P0E3117 DC/DC Converter Voltage Sensor "A" (VL) Circuit Voltage Above Threshold
      P0E311F DC/DC Converter Voltage Sensor "A"(VL) Circuit Intermittent
      P0E5717 DC/DC Converter Voltage Sensor "A"(VL) Circuit Voltage Above Threshold

      Tech Tips


      • P31B300 may be output as a result of the malfunction indicated by the DTCs above.


        1. The chart above is listed in inspection order of priority.

        2. Check DTCs that are output at the same time by following the listed order. (The main cause of the malfunction can be determined without performing unnecessary inspections.)

    5. Turn the power switch off.


    B

    GO TO DTC CHART (HYBRID CONTROL SYSTEM) Click here

    C

    GO TO DTC CHART (MOTOR GENERATOR CONTROL SYSTEM) Click here

    A

  2. READ VALUE USING GTS (HYBRID BATTERY VOLTAGE)


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Enter the following menus: Powertrain / HV battery / Data List / Hybrid Battery Voltage

    4. Read the Data List.


      Powertrain > HV Battery > Data List
      Tester Display
      Hybrid Battery Voltage

      Note

      Be sure not to measure when the power switch is on (READY).

    5. Make a note of the data list item "Hybrid Battery Voltage".

    6. Turn the power switch off.

      Result
      Proceed to
      NEXT

    NEXT

  3. CHECK HV BATTERY

    CAUTION:

    Be sure to wear insulated gloves.


    1. Check that the service plug grip is not installed.

      Note

      After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair manual because this may cause a malfunction.

    2. Remove the HV battery upper cover panel.

      Click here

    3. B004X2RN03

      Disconnect the z33 HV battery high voltage connector from the HV battery junction block assembly (positive side).

      Note

      Insulate each disconnected high-voltage connector with insulating tape. Wrap the connector from the wire harness side to the end of the connector.

    4. B004XIPC02
      *a

      No. 2 HV Supply Stack Sub-assembly Connector

      (to HV battery junction block assembly (positive side))
      *b

      Service Plug Grip Removed

      (Service Plug Grip Connecting Terminals)

      Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition
      z33-1 - 1 Power switch off

      CAUTION:

      Do not allow the probes of the electrical tester to contact each other during this inspection.

    5. Check the value in the data list "Hybrid Battery Voltage" and the hybrid battery voltage value that was actually measured.

      Result
      Result Proceed to
      When the difference between "Hybrid Battery Voltage" in the Data List and the measurement value of the HV battery voltage is 5 V or more. A
      Other than above B

    6. Reconnect the z33 HV battery high voltage connector from the HV battery junction block assembly (positive side).

    7. Install the HV battery upper cover panel.


    B

    CHECK FREEZE FRAME DATA (HYBRID CONTROL) Click here

    A

  4. REPLACE BATTERY VOLTAGE SENSOR (for Upper Side), BATTERY VOLTAGE SENSOR (for Lower Side) AND BATTERY ECU ASSEMBLY

    Battery voltage sensor: Click here

    Battery ECU assembly: Click here

    Result
    Proceed to
    NEXT

    NEXT

    REPLACE NO. 1 HV SUPPLY STACK SUB-ASSEMBLY AND NO. 2 HV SUPPLY STACK SUB-ASSEMBLY Click here

  5. CHECK FREEZE FRAME DATA (HYBRID CONTROL)


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.

    4. Read the freeze frame data of DTC P31B300.


      Powertrain > Hybrid Control > Trouble Codes
      Result
      Result Proceed to
      "Hybrid Battery Voltage" is 352 V or less. A
      Other than above B

    5. Turn the power switch off.


    A

    REPLACE INVERTER WITH CONVERTER ASSEMBLY Click here

    B

  6. REPLACE BATTERY VOLTAGE SENSOR (for Upper Side), BATTERY VOLTAGE SENSOR (for Lower Side) AND BATTERY ECU ASSEMBLY

    Battery voltage sensor: Click here

    Battery ECU assembly: Click here

    Result
    Proceed to
    NEXT

    NEXT

    REPLACE NO. 1 HV SUPPLY STACK SUB-ASSEMBLY AND NO. 2 HV SUPPLY STACK SUB-ASSEMBLY Click here