HYBRID CONTROL SYSTEM, Diagnostic DTC:P0AA1-231

DTC Code DTC Name
P0AA1-231 Battery Positive Contactor Circuit Stuck Closed

DTC SUMMARY


  1. MALFUNCTION DESCRIPTION

    The EV control ECU detects a stuck closed malfunction of a system main relay on the EV battery positive side.

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


      Inside of inverter voltage sensor (VH) circuit malfunction

    • Voltage sensor (VH) malfunction

    • Motor generator control ECU (MG ECU) malfunction

    • Communication (wire harness) malfunction


      High voltage system malfunction

    • EV battery junction block assembly malfunction


      Low-voltage circuit (12 V) malfunction

    • EV control ECU malfunction

    • EV battery junction block assembly malfunction

    • Low voltage wire harness malfunction

    • Low voltage connector malfunction

DESCRIPTION

Refer to the description for DTC P0AE6-225.

Click here

DTC No. Detection Item DTC Detection Condition Trouble Area Warning Indicate
P0AA1-231 Battery Positive Contactor Circuit Stuck Closed

System main relay stuck closed malfunction (EV battery positive (+) terminal side)

(1 trip detection logic)

  • EV battery junction block assembly

  • Inverter with converter assembly

  • EV control ECU

  • Wire harness or connector

Master Warning Light:

Comes on
Related Data List
DTC No. Data List
P0AA1-231

  • VB-Battery Voltage

  • VH-Voltage after Boosting

The following items can be helpful when performing repairs:


WIRING DIAGRAM

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

Click here

CAUTION / NOTICE / HINT

CAUTION:


  • When troubleshooting DTC P0AA1-231, use either a tool wrapped with vinyl insulation tape or an insulated tool (It is extremely dangerous when a high-voltage charge passes through a non-insulated tool causing a short).

  • B006JFB
    B006JM4

    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 grips from both FC stack assembly and EV battery.


    • Inspecting the high-voltage system

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

    • Disconnecting the low voltage connector of the EV battery

    • Disconnecting the low voltage connector of the FC stack assembly

    • Disconnecting the low voltage connector of the FC converter assembly

      Tech Tips

      No removal order is specified for the service plug grips of the FC stack assembly and EV battery.

  • B006JBZ

    After removing the service plug grip from the EV battery, 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 grip from the FC stack assembly, store it in a safe location and use the "HIGH-VOLTAGE, DO NOT TOUCH" sign to notify other technicians that you are working on the high-voltage system.

  • B000ZMTC04
    *a Without waiting for 10 minutes

    After removal of the service plug grips of both FC stack assembly and EV battery, wait for at least 10 minutes before touching the high-voltage connectors and 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

    At least 10 minutes are necessary to discharge the high-voltage capacitors inside the inverter with converter assembly and FC stack 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

  • Before performing repairs, clearing the DTCs or disconnecting and reconnecting the auxiliary battery terminal and then turning the power switch on (READY) could cause a malfunction, so make sure not to turn the power switch on (READY).

  • When reinstalling the service plug grip to the FC stack assembly or the EV battery, slide the lever of the service plug until the letters "UNLOCK" are completely hidden, and insert it firmly.

    Click here

  • When the vehicle is parked with the power switch off, if the FC control ECU judges that the FC stack temperature will go below 0°C (32°F), it activates the FC air compressor, hydrogen pump and FC cooling water pump for a maximum of 180 seconds and drains water from the FC stack assembly. When performing inspection or repairs with the power switch off (not on (IG) or on (READY)), disconnect the cable from the negative (-) auxiliary battery terminal before performing work (If the auxiliary battery voltage is needed to conduct inspection, warm up the FC system beforehand).

Tech Tips


  • If DTC P0AA1-231 is output, the power switch cannot be turned on (READY).

  • After the repair, clear the DTCs and perform the following procedure to check that DTCs are not output.


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

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

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

PROCEDURE


  1. CHECK DTC OUTPUT (EV)


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Enter the following menus: Powertrain / EV / Trouble Codes.

    4. Check for DTCs.


      Powertrain > EV > Trouble Codes
      Result
      Result Proceed to
      P0AA1-231 only is output, or DTCs except the ones in the table below are also output. A
      Any of the following DTCs including pending DTCs are also output. B
      Malfunction Content Relevant DTC
      Microcomputer malfunction P0A1B-163, 164, 168, 193, 511, 512, 661, 786, 794, 795, 796 Drive Motor "A" Control Module
      P0A1D-148 EV Control Module
      P1D8F-474, 475, 476, 477, 479, 481, 482, 483, 484 FC Air Compressor Motor "A" Control Module
      P324E-788 Motor CPU Power Relay Sense Circuit Intermittent No Continuity
      Power source circuit malfunction P2511-149 EV CPU Power Relay Sense Circuit Intermittent No Continuity
      Communication system malfunction U0110 (all INF codes)*1 Lost Communication with Drive Motor Control Module "A"
      Sensor and actuator circuit malfunction P0A3F-243 Drive Motor "A" Position Sensor Circuit
      P0A40-500 Drive Motor "A" Position Sensor Circuit Range/Performance
      P0A41-245 Drive Motor "A" Position Sensor Circuit Low
      P1D75-450 FC Air Compressor Motor "A" Position Sensor Circuit
      P1D76-450 FC Air Compressor Motor "A" Position Sensor Circuit Range/Performance
      P1D77-450 FC Air Compressor Motor "A" Position Sensor Circuit Low
      P0A78-266, 267, 586 Drive Motor "A" Inverter Performance
      P0A94-442 Boosting Converter Performance
      P0ADC-226 Battery Positive Contactor Control Circuit High
      P0C76-523 EV Battery System Discharge Time Too Long
      System malfunction P3004-132 High Voltage Power Resource

      Tech Tips


      • *1: If any INF codes are output for this DTC, refer to the corresponding diagnostic procedure.

      • P0AA1-231 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)

    A

  2. FREEZE FRAME DATA (EV)


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Enter the following menus: Powertrain / EV / Trouble Codes.


      Powertrain > EV > Trouble Codes

    4. Read the freeze frame data of DTC P0AA1-231.

      Result
      Result Proceed to
      "VL-Voltage before Boosting" is 55 V or more. A
      "VL-Voltage before Boosting" is less than 55 V. B

    5. Turn the power switch off.


    B

    REPLACE INVERTER WITH CONVERTER ASSEMBLY

    A

  3. CHECK CONNECTOR CONNECTION CONDITION (EV CONTROL ECU ASSEMBLY CONNECTOR)

    Result
    Proceed to
    OK
    NG

    1. A01MGTOC01
      *A for LHD
      *B for RHD

      Check the connector connections and contact pressure of the relevant terminals for the EV control ECU connectors.

      Click here

      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. B000ZOWC01
      *A for LHD
      *B for RHD

      Check the connector connections and contact pressure of the relevant terminals for the GQ1 floor wire connector.

      OK
      The connectors are connected securely and there are no contact pressure problems.
      Result
      Proceed to
      OK
      NG

    OK

    GO TO STEP 7 Click here

    NG

  6. CONNECT SECURELY

    Result
    Proceed to
    NEXT

    NEXT

  7. CHECK CONNECTOR CONNECTION CONDITION (EV BATTERY JUNCTION BLOCK ASSEMBLY CONNECTOR)

    CAUTION:

    Be sure to wear insulated gloves.


    1. Check that the service plug grip is not installed to FC stack assembly and EV battery.

      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. 4 EV battery shield panel.

    3. B000ZHME01

      Check the connection condition of the EV battery junction block connector and the contact pressure of each terminal. Check the terminals for deformation, and check the connector for water ingress and foreign matter.

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

    4. Install the No. 4 EV battery shield panel.

      Result
      Proceed to
      OK
      NG

    OK

    GO TO STEP 9 Click here

    NG

  8. CONNECT SECURELY

    Result
    Proceed to
    NEXT

    NEXT

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


    1. Check the installation condition of the ground wires GA, GD and QB.

      OK
      The ground wires GA, GD and QB are securely installed.
      Result
      Proceed to
      OK
      NG

    OK

    GO TO STEP 11 Click here

    NG

  10. CONNECT SECURELY

    Result
    Proceed to
    NEXT

    NEXT

  11. CHECK HARNESS AND CONNECTOR (EV CONTROL ECU - EV BATTERY JUNCTION BLOCK ASSEMBLY)

    CAUTION:

    Be sure to wear insulated gloves.


    1. Check that the service plug grip is not installed to FC stack assembly and EV battery.

      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. 4 EV battery shield panel.

    3. Disconnect the EV junction block assembly connector.

    4. Disconnect the EV control ECU connector.

    5. B000ZMDC12
      *a

      Rear view of wire harness connector

      (to EV Control ECU)
      *b

      Rear view of wire harness connector

      (to EV Battery Junction Block Assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G45-4 (SMRB) - Q16-1 (SMRB) Power switch off Below 1 Ω
      G45-4 (SMRB) and Q16-1 (SMRB) - Body ground and other terminals Power switch off 10 kΩ or higher

    6. Reconnect the EV control ECU connector.

    7. Reconnect the EV junction block assembly connector.

    8. Install the No. 4 EV battery shield panel.

      Result
      Proceed to
      OK
      NG

    OK

    GO TO STEP 13 Click here

    NG

  12. REPAIR OR REPLACE HARNESS OR CONNECTOR

    Result
    Proceed to
    NEXT

    NEXT

  13. CHECK HARNESS AND CONNECTOR (EV BATTERY JUNCTION BLOCK ASSEMBLY - BODY GROUND)

    CAUTION:

    Be sure to wear insulated gloves.


    1. Check that the service plug grip is not installed to FC stack assembly and EV battery.

      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. 4 EV battery shield panel.

    3. Disconnect the EV battery junction block assembly connector.

    4. B000ZG5C04
      *a

      Rear view of wire harness connector

      (to EV Battery Junction Block Assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Q16-2 (GND) - Body ground Power switch off Below 1 Ω

    5. Reconnect the EV battery junction block assembly connector.

    6. Install the No. 4 EV battery shield panel.

      Result
      Proceed to
      OK
      NG

    OK

    GO TO STEP 15 Click here

    NG

  14. REPAIR OR REPLACE HARNESS OR CONNECTOR

    Result
    Proceed to
    NEXT

    NEXT

  15. INSPECT EV BATTERY JUNCTION BLOCK ASSEMBLY (SMRB)

    CAUTION:

    Be sure to wear insulated gloves.


    1. Check that the service plug grip is not installed to FC stack assembly and EV battery.

      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. 4 EV battery shield panel.

    3. Disconnect the EV battery junction block assembly connector.

    4. B000ZFGC20
      *a

      Component without harness connected

      (EV Battery Junction Block Assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Q16-1 (SMRB) - Q16-2 (GND) -40 to 80°C (-40 to 176°F) 25.0 to 59.0 Ω

    5. Reconnect the EV battery junction block assembly connector.

    6. Install the No. 4 EV battery shield panel.

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE EV BATTERY JUNCTION BLOCK ASSEMBLY Click here

    OK

  16. CHECK EV BATTERY JUNCTION BLOCK ASSEMBLY (SMRB)

    CAUTION:

    Be sure to wear insulated gloves.


    1. Check that the service plug grip is not installed to FC stack assembly and EV battery.

      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 EV battery shield sub-assembly.

      Click here

    3. Disconnect the frame wire connector from the EV battery junction block assembly.

    4. B000ZEUC05
      *a EV Battery Junction Block Assembly

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

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

      Tech Tips


      • If a system main relay is stuck closed, inspect the EV 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 EV battery junction block assembly must be replaced. Measuring resistance can determine that this is either a present or past malfunction.

    5. Reconnect the frame wire connector to the EV battery junction block assembly.

    6. Install the No. 1 EV battery shield sub-assembly.

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE EV BATTERY JUNCTION BLOCK ASSEMBLY Click here

    OK

  17. REPLACE EV BATTERY JUNCTION BLOCK ASSEMBLY

    Click here

    Result
    Proceed to
    NEXT

    NEXT

    GO TO STEP 20 Click here

  18. REPLACE EV BATTERY JUNCTION BLOCK ASSEMBLY

    Click here

    Result
    Proceed to
    NEXT

    NEXT

    GO TO STEP 20 Click here

  19. REPLACE EV BATTERY JUNCTION BLOCK ASSEMBLY

    Click here

    Result
    Proceed to
    NEXT

    NEXT

  20. CHECK EV CONTROL ECU (CHECK FOR NORMAL OPERATION)


    1. Install the FC stack service plug grip and service plug grip (for EV).

    2. Turn the power switch on (IG).

    3. Clear the DTCs.


      Powertrain > EV > 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 / EV / Data List / VL-Voltage before Boosting, VB-Battery Voltage.

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


      Powertrain > EV > Data List
      Tester Display
      VL-Voltage before Boosting
      VB-Battery Voltage
      Result
      Result Proceed to
      Difference between "VB-Battery Voltage" and "VL-Voltage before Boosting" is always less than 100 V. A
      Difference between "VB-Battery Voltage" and "VL-Voltage before Boosting" is 100 V or more. B

    8. Turn the power switch off.


    A

    COMPLETED

    B

    REPLACE EV CONTROL ECU AND EV BATTERY JUNCTION BLOCK ASSEMBLY EV control ECU: REPLACE EV CONTROL ECU AND EV BATTERY JUNCTION BLOCK ASSEMBLY Click here
    REPLACE EV CONTROL ECU AND EV BATTERY JUNCTION BLOCK ASSEMBLY EV battery junction block assembly: REPLACE EV CONTROL ECU AND EV BATTERY JUNCTION BLOCK ASSEMBLY Click here