HYBRID CONTROL SYSTEM, Diagnostic DTC:P0AA373

DTC Code DTC Name
P0AA373 Hybrid/EV Battery Negative Contactor Actuator Stuck Closed

DTC SUMMARY


  1. MALFUNCTION DESCRIPTION

    The hybrid vehicle control ECU detects a stuck closed malfunction of a system main relay on the HV battery negative side.

    The cause of this malfunction may be one of the following:


      Inverter voltage sensor (VH) internal circuit malfunction

    • Voltage sensor (VH) malfunction

    • Motor generator control ECU (MG ECU) malfunction

    • Communication (wire harness) malfunction


      High voltage system malfunction

    • HV battery junction block assembly malfunction


      Low-voltage circuit (12 V) malfunction

    • Hybrid vehicle control ECU malfunction

    • HV battery junction block assembly malfunction

    • Low voltage wire harness malfunction

    • Low voltage connector malfunction

DESCRIPTION

Refer to the description for DTC P0AE411.

Click here

DTC No. Detection Item DTC Detection Condition Trouble Area MIL Warning Indicate
P0AA373 Hybrid/EV Battery Negative Contactor Actuator Stuck Closed

Even the system main relay of HV battery negative (-) terminal side is turned off, the inverter voltage (VH) does not drop.

(1 trip detection logic)

  • HV battery junction block assembly

  • Inverter with converter assembly

  • Hybrid vehicle control ECU

  • Wire harness or connector

 Does not come on

Master Warning Light:

Comes on
Related Data List
DTC No. Data List
P0AA373

  • Hybrid Battery Voltage

  • VH-Voltage after Boosting

  • VL-Voltage before Boosting

CONFIRMATION DRIVING PATTERN

Tech Tips

After repairs have been completed, clear the DTCs 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 3 minutes or more.

    Tech Tips

    According to the display on the GTS, read the Data List and monitor the values of "Hybrid Battery Voltage" and "VL-Voltage before Boosting" for 3 minutes. If the difference between "Hybrid Battery Voltage" and "VL-Voltage before Boosting" is always less than 100 V, the vehicle has returned to normal.

  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 or N/A, perform driving pattern again.

WIRING DIAGRAM

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

Click here

CAUTION / NOTICE / HINT

CAUTION:


  • Before inspecting the high-voltage system or disconnecting the low voltage connector of the inverter with converter assembly, take safety precautions such as wearing insulated gloves and removing the service plug grip to prevent electrical shocks. After removing the service plug grip, put it in your pocket to prevent other technicians from accidentally reconnecting it while you are working on the high-voltage system.

  • 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.

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

  • If the DTCs are cleared or the cable is disconnected and reconnected to the negative (-) auxiliary battery terminal before performing repairs, turning the power switch on (READY) may cause a malfunction. Do not turn the power switch on (READY).

Tech Tips

If DTC P0AA373 is output, the power switch cannot be turned on (READY).

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.


      Powertrain > Hybrid Control > Trouble Codes
      Powertrain > Motor Generator > Trouble Codes

    4. Check for DTCs.

      Result
      Result Proceed to
      P0AA373 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
      Microcomputer malfunction Hybrid control system P060647 Hybrid/EV Powertrain Control Module Processor Watchdog / Safety MCU Failure
      P060687 Hybrid/EV Powertrain Control Module Processor to Monitoring Processor Missing Message
      P060A47 Hybrid/EV Powertrain Control Module Monitoring Processor Watchdog / Safety MCU Failure
      P060A87 Hybrid/EV Powertrain Control Module Processor from Monitoring Processor Missing Message
      P0A1B49 Drive Motor "A" Control Module Internal Electronic Failure
      P1C9E9F Hybrid/EV System Reset Stuck Off
      P0AFC96 Hybrid/EV Battery Sensor Module Component Internal Failure
      P0AFC00 Hybrid/EV Battery Sensor Module
      Motor generator control system P0A1B1F Generator Control Module Circuit Intermittent
      P0A1A47 Generator Control Module Watchdog / Safety μC Failure
      P0A1A49 Generator Control Module Internal Electronic Failure
      P1C2A1C Generator A/D Converter Circuit Circuit Voltage Out of Range
      P1C2A49 Generator A/D Converter Circuit Internal Electronic Failure
      P1C2B1C Drive Motor "A" Control Module A/D Converter Circuit Voltage Out of Range
      P1C2B49 Drive Motor "A" Control Module A/D Converter Circuit Internal Electronic Failure
      P1CAC49 Generator Position Sensor Internal Electronic Failure
      P1CAD49 Drive Motor "A" Position Sensor Internal Electronic Failure
      P1CAF38 Generator Position Sensor REF Signal Cycle Malfunction Signal Frequency Incorrect
      P1CB038 Drive Motor "A" Position Sensor REF Signal Frequency Incorrect
      P313383 Communication Error from Generator to Drive Motor "A" Value of Signal Protection Calculation Incorrect
      P313386 Communication Error from Generator to Drive Motor "A" Signal Invalid
      P313387 Communication Error from Generator to Drive Motor "A" Missing Message
      Power source circuit malfunction Hybrid control system P0AFC16 Hybrid/EV Battery Sensor Module Circuit Voltage Below Threshold
      Motor generator control system P06D61C Generator Control Module Offset Power Circuit Voltage Out of Range
      P06B01C Generator Control Module Position Sensor REF Power Source Circuit Voltage Out of Range
      Communication system malfunction Hybrid control system P312387 Lost Communication with Drive Motor Control Module "A" from Hybrid/EV Control Module Missing Message
      U029A87 Lost Communication with Hybrid/EV Battery Sensor Module Missing Message
      Sensor and actuator circuit malfunction Hybrid control system P0AD911 Hybrid/EV Battery Positive Contactor Circuit Short to Ground
      P0AD915 Hybrid/EV Battery Positive Contactor Circuit Short to Auxiliary Battery or Open
      P0ADD11 Hybrid/EV Battery Negative Contactor Circuit Short to Ground
      P0ADD15 Hybrid/EV Battery Negative Contactor Circuit Short to Auxiliary Battery or Open
      P0AE411 Hybrid/EV Battery Precharge Contactor Circuit Short to Ground
      P0AE415 Hybrid/EV Battery Precharge Contactor Circuit Short to Auxiliary Battery or Open
      P0B3B14 Hybrid/EV Battery Voltage Sensor "A" Circuit Short to Ground or Open
      P0B4014 Hybrid/EV Battery Voltage Sensor "B" Circuit Short to Ground or Open
      P0B4514 Hybrid/EV Battery Voltage Sensor "C" Circuit Short to Ground or Open
      P0B4A14 Hybrid/EV Battery Voltage Sensor "D" Circuit Short to Ground or Open
      P0B4F14 Hybrid/EV Battery Voltage Sensor "E" Circuit Short to Ground or Open
      P0B5414 Hybrid/EV Battery Voltage Sensor "F" Circuit Short to Ground or Open
      P0B5914 Hybrid/EV Battery Voltage Sensor "G" Circuit Short to Ground or Open
      P0B5E14 Hybrid/EV Battery Voltage Sensor "H" Circuit Short to Ground or Open
      P0B6314 Hybrid/EV Battery Voltage Sensor "I" Circuit Short to Ground or Open
      P0B6814 Hybrid/EV Battery Voltage Sensor "J" Circuit Short to Ground or Open
      P308A13 Hybrid/EV Battery Voltage Sensor All Circuit Open
      P0AFC62 Hybrid/EV Battery Sensor Module Signal Compare Failure
      P308A12 Hybrid/EV Battery Voltage Sensor All Circuit Short to Auxiliary Battery
      Motor generator control system P0A3F16 Drive Motor "A" Position Sensor Circuit Voltage Below Threshold
      P0A4B16 Generator Position Sensor Circuit Voltage Below Threshold
      P0A4B21 Generator Position Sensor Signal Amplitude < Minimum
      P0A4B22 Generator Position Sensor Signal Amplitude > Maximum
      P0C5013 Drive Motor "A" Position Sensor Circuit "A" Circuit Open
      P0C5016 Drive Motor "A" Position Sensor Circuit "A" Circuit Voltage Below Threshold
      P0C5017 Drive Motor "A" Position Sensor Circuit "A" Circuit Voltage Above Threshold
      P0C5A13 Drive Motor "A" Position Sensor Circuit "B" Circuit Open
      P0C5A16 Drive Motor "A" Position Sensor Circuit "B" Circuit Voltage Below Threshold
      P0C5A17 Drive Motor "A" Position Sensor Circuit "B" Circuit Voltage Above Threshold
      P0C6413 Generator Position Sensor Circuit "A" Circuit Open
      P0C6416 Generator Position Sensor Circuit "A" Circuit Voltage Below Threshold
      P0C6417 Generator Position Sensor Circuit "A" Circuit Voltage Above Threshold
      P0C6913 Generator Position Sensor Circuit "B" Circuit Open
      P0C6916 Generator Position Sensor Circuit "B" Circuit Voltage Below Threshold
      P0C6917 Generator Position Sensor Circuit "B" Circuit Voltage Above Threshold
      System malfunction Hybrid control system P0C7600 Hybrid/EV Battery System Discharge Time Too Long
      P0D2D1C Drive Motor "A" Inverter Voltage Sensor Voltage Out of Range
      P1C8349 High Voltage Power Resource Circuit Voltage Sensor after Boosting Malfunction
      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
      P1CB69E Drive Motor "A" Inverter Voltage Sensor (VH) Stuck On

      Tech Tips


      • P0AA373 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. 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 P0AA373.


      Powertrain > Hybrid Control > DTC(P0AA373) > Freeze Frame Data
      Tester Display
      VL-Voltage before Boosting
      VH-Voltage after Boosting

      Note

      As freeze frame data is stored immediately before and after a DTC is stored, make sure to only read the values for the moment the DTC was stored ("0(s)").

      Result
      Result Proceed to
      Difference between "VL-Voltage before Boosting" and "VH-Voltage after Boosting" is less than 76 V. A
      Difference between "VL-Voltage before Boosting" and "VH-Voltage after Boosting" is 76 V or more. B

      Tech Tips

      If VH-Voltage after Boosting is output even when an off command is being sent to the system main relay (positive side), P0AA373 is output. If the difference between the "VL-Voltage before Boosting" and the "VH-Voltage after Boosting" is large, it is determined that there is an inverter (VH sensor) malfunction.

    5. Turn the power switch off.


    B

    REPLACE INVERTER WITH CONVERTER ASSEMBLY Click here

    A

  3. CHECK CONNECTOR CONNECTION CONDITION (HYBRID VEHICLE CONTROL ECU CONNECTOR)


    1. Check the connector connections and contact pressure of the relevant terminals for the hybrid vehicle control ECU connectors.

      Tech Tips

      Click here

      B004P9FC01
      *A for LHD *B for RHD
      OK
      The connectors are connected securely and there are no contact pressure problems.
      Result
      Proceed to
      OK
      NG

    OK

    GO TO STEP 5 Click here

    NG

  4. CONNECT SECURELY

    Result
    Proceed to
    NEXT

    NEXT

  5. CHECK CONNECTOR CONNECTION CONDITION (FLOOR WIRE CONNECTOR)


    1. B004OUBC01
      *A for LHD
      *B for RHD

      Check the connection condition of the MF2 or MF1 floor wire connector and the contact pressure of each terminal. Check the terminals for deformation, and check the connector for water ingress and foreign matter.

      Tech Tips

      Click here

      OK
      - The connector is connected securely.
      - The terminals are not deformed and are connected securely.
      - No water or foreign matter in the connector.
      Result
      Result Proceed to
      OK A
      NG (The connector is not connected securely.) B
      NG (The terminals are not making secure contact or are deformed, or water or foreign matter exists in the connector.) C

    A

    GO TO STEP 8 Click here

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR Click here

    B

  6. CONNECT SECURELY

    Result
    Proceed to
    NEXT

    NEXT

    GO TO STEP 8 Click here

  7. REPAIR OR REPLACE HARNESS OR CONNECTOR

    Result
    Proceed to
    NEXT

    NEXT

  8. CHECK CONNECTOR CONNECTION CONDITION (HV BATTERY JUNCTION BLOCK ASSEMBLY CONNECTOR)

    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 No. 1 HV battery cover panel RH.

      Tech Tips

      Click here

    3. B004PQ3N02

      Check the connector connections and contact pressure of the relevant terminals of the M37 HV battery junction block assembly connector.

      Tech Tips

      Click here

      OK
      The connectors are connected securely and there are no contact pressure problems.

    4. Install the No. 1 HV battery cover panel RH.

      Result
      Proceed to
      OK
      NG

    OK

    GO TO STEP 10 Click here

    NG

  9. CONNECT SECURELY

    Result
    Proceed to
    NEXT

    NEXT

  10. CHECK GROUND WIRE CONNECTION CONDITION (SMR ACTIVATION LOW-VOLTAGE CIRCUIT)


    1. Check the installation condition of the ground wire MD.

      OK
      The ground wire MD is securely installed.
      Result
      Proceed to
      OK
      NG

    OK

    GO TO STEP 12 Click here

    NG

  11. CONNECT SECURELY

    Result
    Proceed to
    NEXT

    NEXT

  12. CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - HV BATTERY JUNCTION BLOCK ASSEMBLY)

    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 No. 1 HV battery cover panel RH.

      Tech Tips

      Click here

    3. Disconnect the M37 HV battery junction block assembly connector.

    4. Disconnect the F2 hybrid vehicle control ECU connector.

    5. B004OMTC15
      *a

      Front view of wire harness connector

      (to Hybrid Vehicle Control ECU)
      *b

      Front view of wire harness connector

      (to HV Battery Junction Block Assembly)

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      F2-13 (SMRG) - M37-4 (SMRG) Power switch off Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      F2-13 (SMRG) and M37-4 (SMRG) - Body ground and other terminals Power switch off 10 kΩ or higher

    6. Reconnect the F2 hybrid vehicle control ECU connector.

    7. Reconnect the M37 HV battery junction block assembly connector.

    8. Install the No. 1 HV battery cover panel RH.

      Result
      Proceed to
      OK
      NG

    OK

    GO TO STEP 14 Click here

    NG

  13. REPAIR OR REPLACE HARNESS OR CONNECTOR

    Result
    Proceed to
    NEXT

    NEXT

  14. CHECK HARNESS AND CONNECTOR (HV BATTERY JUNCTION BLOCK ASSEMBLY - BODY GROUND)

    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 No. 1 HV battery cover panel RH.

      Tech Tips

      Click here

    3. Disconnect the M37 HV battery junction block assembly connector.

    4. B004QCIC04
      *a

      Front view of wire harness connector

      (to HV Battery Junction Block Assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      M37-3 (GND) - Body ground Power switch off Below 1 Ω

    5. Reconnect the M37 HV battery junction block assembly connector.

    6. Install the No. 1 HV battery cover panel RH.

      Result
      Proceed to
      OK
      NG

    OK

    GO TO STEP 16 Click here

    NG

  15. REPAIR OR REPLACE HARNESS OR CONNECTOR

    Result
    Proceed to
    NEXT

    NEXT

  16. INSPECT HV BATTERY JUNCTION BLOCK ASSEMBLY (SMRG)

    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 No. 1 HV battery cover panel RH.

      Tech Tips

      Click here

    3. Disconnect the M37 HV battery junction block assembly connector.

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

      B004PMLC29
      *a

      Component without harness connected

      (HV Battery Junction Block Assembly)

      		 - -
      Standard Resistance
      Tester Connection Condition Specified Condition
      M37-4 (SMRG) - M37-3 (GND) -40 to 80°C (-40 to 176°F) 20.6 to 40.8 Ω

    5. Reconnect the M37 HV battery junction block assembly connector.

    6. Install the No. 1 HV battery cover panel RH.

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE HV BATTERY JUNCTION BLOCK ASSEMBLY Click here

    OK

  17. CHECK HV BATTERY JUNCTION BLOCK ASSEMBLY (SMRG)

    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 No. 1 HV battery cover panel RH.

      Tech Tips

      Click here

    3. B004PHQ

      Disconnect the 2 HV floor under wire connectors from the HV battery junction block assembly.

    4. Disconnect the 2 HV battery high voltage connectors from the HV battery junction block assembly.

      Note

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

    5. B004PC6C05
      *a

      Component without harness connected

      (HV Battery Junction Block Assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      S3-1 (CEI) - z12-1 (-) Power switch off 10 kΩ or higher

      Tech Tips


      • If a system main relay is stuck closed, inspect the HV battery junction block assembly without removing it from the vehicle, in order to keep the relay closed.

      • If the result of reading the freeze frame data is A, the HV battery junction block assembly must be replaced. Measuring resistance can determine that this is either a present or past malfunction.

    6. Reconnect the 2 HV battery high voltage connectors.

    7. Reconnect the 2 HV floor under wire connectors.

    8. Install the No. 1 HV battery cover panel RH.

      Result
      Result Judgment Proceed to
      OK Past malfunction A
      NG Present malfunction B

    B

    REPLACE HV BATTERY JUNCTION BLOCK ASSEMBLY Click here

    A

  18. REPLACE HV BATTERY JUNCTION BLOCK ASSEMBLY

    Tech Tips

    Click here

    Result
    Proceed to
    NEXT

    NEXT

    GO TO STEP 21 Click here

  19. REPLACE HV BATTERY JUNCTION BLOCK ASSEMBLY

    Tech Tips

    Click here

    Result
    Proceed to
    NEXT

    NEXT

    GO TO STEP 21 Click here

  20. REPLACE HV BATTERY JUNCTION BLOCK ASSEMBLY

    Tech Tips

    Click here

    Result
    Proceed to
    NEXT

    NEXT

  21. CHECK HYBRID VEHICLE CONTROL ECU (CHECK FOR NORMAL OPERATION)


    1. Install the service plug grip.

    2. Turn the power switch on (IG).

    3. Clear the DTCs.


      Powertrain > Hybrid Control > Clear DTCs

    4. Turn the power switch off and wait for 30 seconds or more.

    5. Turn the power switch on (READY).

    6. Enter the following menus: Powertrain / Hybrid Control / Data List / Hybrid Battery Voltage, VL-Voltage before Boosting.


      Powertrain > Hybrid Control > Data List
      Tester Display
      VL-Voltage before Boosting
      Hybrid Battery Voltage

    7. According to the display on the GTS, read the Data List and monitor the values of "Hybrid Battery Voltage" and "VL-Voltage before Boosting" for 3 minutes.

      Result
      Result Proceed to
      Difference between "Hybrid Battery Voltage" and "VL-Voltage before Boosting" is always less than 100 V. A
      Difference between "Hybrid Battery Voltage" and "VL-Voltage before Boosting" is 100 V or more. B

    8. Turn the power switch off.


    A

    END

    B

    REPLACE HYBRID VEHICLE CONTROL ECU AND HV BATTERY JUNCTION BLOCK ASSEMBLY HYBRID VEHICLE CONTROL ECU: Click here
    REPLACE HYBRID VEHICLE CONTROL ECU AND HV BATTERY JUNCTION BLOCK ASSEMBLY HV BATTERY JUNCTION BLOCK ASSEMBLY: Click here