HYBRID BATTERY SYSTEM, Diagnostic DTC:P31B300

DTC Code DTC Name
P31B300 Hybrid/EV Battery Voltage High

DESCRIPTION

If the voltage of any HV battery cell exceeds the threshold, charging will be prohibited. If charging cannot be prohibited due to an HV battery control system malfunction, this DTC will be stored.

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

Charging cannot be prohibited when the voltage of any HV battery cell has exceeded the specified threshold.

(1 trip detection logic)

  • Hybrid vehicle control ECU

  • No. 1 HV battery junction block assembly

  • No. 2 HV battery junction block assembly

 Comes on

Master Warning Light:

Comes on
Related Data List
DTC No. Data List
P31B300 Hybrid Battery Cell 1 to 95 Voltage

The following items can be helpful when performing repairs:


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. Drive the vehicle on urban roads for approximately 10 minutes.

  7. Enter the following menus: Powertrain / HV Battery / 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 or N/A, perform driving pattern again.

CAUTION / NOTICE / HINT

CAUTION:


  • B006HUP

    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

    • Disconnecting the low voltage connector of the electric vehicle charger assembly

    • Disconnecting the low voltage connector of the solar energy control unit

  • B006IQP

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

  • B006HQC

    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.

  • B006IVPC02
    *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 and the electric vehicle charger assembly.

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

PROCEDURE


  1. CHECK DTC OUTPUT (HV BATTERY, HYBRID CONTROL)


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

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

    4. Check for DTCs.


      Powertrain > HV Battery > Trouble Codes
      Powertrain > Hybrid Control > Trouble Codes
      Result
      Result Proceed to
      "P31B300" only is output. A
      DTCs except "P31B300" of hybrid battery system are output. B
      DTCs except "P31B300" of hybrid control system are output. C

    5. Turn the power switch off.


    B

    GO TO DTC CHART (HYBRID BATTERY SYSTEM) Click here

    C

    GO TO DTC CHART (HYBRID CONTROL SYSTEM) Click here

    A

  2. 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 / HV Battery / Trouble Codes.

    4. Read the freeze frame data of DTC P31B300.


      Powertrain > HV Battery > Trouble Codes
      Result
      Result Proceed to
      OFF is displayed for "Ready Signal", "SMRP Status", "SMRB Status" and "SMRG Status" and -0.5 A or less is displayed for "Hybrid Battery Current". A
      Other than above B

      Tech Tips

      As the power switch on (IG) state may cause the DTC to be stored, freeze frame data is used to judge the cause of the DTC output.

    5. Turn the power switch off.


    B

    REPLACE HYBRID VEHICLE CONTROL ECU Click here

    A

  3. INSPECT NO. 2 HV BATTERY JUNCTION BLOCK ASSEMBLY (SMRB)

    Result
    Proceed to
    OK
    NG

    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 upper hybrid battery cover sub-assembly.

      Click here

    3. B006INA

      Disconnect the HV floor under wire connector from the No. 2 HV battery junction block assembly.

      Note


      • Before disconnecting the connector, check that it is not loose or disconnected.

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

    4. Disconnect the HV battery high voltage connector from the No. 2 HV battery junction block assembly.

      Note


      • Before disconnecting the connector, check that it is not loose or disconnected.

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

    5. B006H9BC03
      *a

      Component without harness connected

      (No. 2 HV Battery Junction Block Assembly)

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

      Standard Resistance (SMRB)
      Tester Connection Condition Specified Condition
      S3-1 (CBI) - j1-1 (+) Power switch off 10 kΩ or higher

    6. Reconnect the HV battery high voltage connector to the No. 2 HV battery junction block assembly.

    7. Reconnect the HV floor under wire connector to the No. 2 HV battery junction block assembly.

    8. Install the upper hybrid battery cover sub-assembly.

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE NO. 1 HV BATTERY JUNCTION BLOCK ASSEMBLY AND NO. 2 HV BATTERY JUNCTION BLOCK ASSEMBLY Click here

    OK

  4. INSPECT NO. 1 HV BATTERY JUNCTION BLOCK ASSEMBLY (SMRP, SMRG)

    Result
    Proceed to
    OK
    NG

    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 upper hybrid battery cover sub-assembly.

      Click here

    3. B006JAZ

      Disconnect the HV floor under wire connector from the No. 1 HV battery junction block assembly.

      Note


      • Before disconnecting the connector, check that it is not loose or disconnected.

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

    4. Disconnect the HV battery high voltage connector from the No. 1 HV battery junction block assembly.

      Note


      • Before disconnecting the connector, check that it is not loose or disconnected.

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

    5. B006HEOC09
      *a

      Component without harness connected

      (No. 1 HV Battery Junction Block Assembly)

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

      Standard Resistance (SMRP, SMRG)
      Tester Connection Condition Specified Condition
      S2-1 (CEI) - i1-1 (-) Power switch off 10 kΩ or higher

    6. Reconnect the HV battery high voltage connector to the No. 1 HV battery junction block assembly..

    7. Reconnect the HV floor under wire connector to the No. 1 HV battery junction block assembly.

    8. Install the upper hybrid battery cover sub-assembly.

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE NO. 1 HV BATTERY JUNCTION BLOCK ASSEMBLY AND NO. 2 HV BATTERY JUNCTION BLOCK ASSEMBLY Click here

    OK

  5. PERFORM INITIALIZATION (CURRENT SENSOR OFFSET LEARNING)

    Result
    Proceed to
    NEXT

    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (READY).

    3. Perform a road test.

      Note

      Accelerate/decelerate gently. Avoid rapid acceleration/deceleration.

    4. Enter the following menus: Powertrain / HV Battery / Data List / Hybrid Battery Current


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

    5. Drive the vehicle with the value of Data List item "Hybrid Battery Current" between -50 A to 50 A.

      Tech Tips

      Distance and driving time are not specified.

    6. Turn the power switch off and leave the vehicle for 30 seconds or more.

    7. Turn the power switch on (IG).

    8. Enter the following menus: Powertrain / HV Battery / Data List / Hybrid Battery Current


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

    9. Check that the value of "Hybrid Battery Current" is between - 0.5 A and 0.5 A with the power switch on (IG).

      Note


      • If the value is outside the specified range, perform the road test again.

      • This DTC may be output if Current Sensor Offset Learning has not been completed.

      Tech Tips


      • If the power switch is on (IG) and value of "Hybrid Battery Current" is between - 0.5 A and 0.5 A, current sensor offset learning has been completed.

      • Even if the current sensor offset learning is not complete, the current sensor value will be corrected by repeating the road test a maximum of 7 times.

    10. Turn the power switch off.

      Result
      Proceed to
      NEXT

    NEXT

    END