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Home >> Toyota >> 2019 >> RAV4 XLE, FWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 5 (Hybrid Control System (Lithium-Ion Battery) - Diagnostic Codes (1 Of 6)) >> HYBRID CONTROL SYSTEM (for LITHIUM-ION BATTERY) >> DTC P0A1F-94: Hybrid/EV Battery Energy Control Module Unexpected Operation [06/2020 - ] >> Procedure

DTC P0A1F-94: Hybrid/EV Battery Energy Control Module Unexpected Operation [06/2020 - ]: Procedure

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  1. CHECK DTC OUTPUT (HYBRID CONTROL, HV BATTERY) 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Enter the following menus: Powertrain / Hybrid Control and HV Battery / Trouble Codes.
    4. Check for DTCs.

      Powertrain > Hybrid Control > Trouble Codes 

      Powertrain > HV Battery > Trouble Codes 

      Result

      Result Proceed to
      "P0A1F-94" only is output, or DTCs except the ones in the table below are also output. A
      Simultaneous output of DTCs of hybrid control systems other than P0A1F-94. B
      Any of the following DTCs are also output. C
      System Relevant DTC
      Hybrid battery system P1A00-1C Hybrid Battery Stack 2 Cell Voltage Detection Voltage Out of Range
      P301A-1C Hybrid Battery Stack 1 Cell Voltage Detection Voltage Out of Range
    5. Turn the ignition switch off.

    Result: 

    REPLACE BATTERY ECU ASSEMBLY 

    Refer to REMOVAL [06/2020 - 08/2020] , or refer to REMOVAL [08/2020 - 12/2021] , or refer to REMOVAL [12/2021 - 10/2022] , or refer to REMOVAL [10/2022 - 10/2023] , or refer to REMOVAL [10/2023 - ]

    Result: 

    GO TO DTC CHART (HYBRID CONTROL SYSTEM) 

    Refer to DIAGNOSTIC TROUBLE CODE CHART [06/2020 - 12/2021] , or refer to DIAGNOSTIC TROUBLE CODE CHART [12/2021 - 11/2024] , or refer to DIAGNOSTIC TROUBLE CODE CHART [11/2024 - ]

    Result: 

    See step  2

  2. CHECK DTC 
    1. Check the DTCs that were output when the vehicle was brought to the workshop.

      Result

      Result Proceed to
      "P1A00-1C" is also output. A
      "P301A-1C" is also output. B

    Result: 

    See step  6

    Result: 

    See step  3

  3. CHECK CONNECTOR CONNECTION CONDITION (BATTERY ECU ASSEMBLY CONNECTOR) 
    WARNING:

    Be sure to wear insulated gloves and protective goggles.

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

      After removing the service plug grip, do not turn the ignition switch to ON (READY), unless instructed by the appropriate service information because this may cause a malfunction.

    2. Remove the No. 1 HV battery hose.

      Refer to PROCEDURE - Step 23 [06/2020 - 08/2020] , or refer to PROCEDURE - Step 23 [08/2020 - 12/2021] , or refer to PROCEDURE - Step 23 [12/2021 - 10/2022] , or refer to PROCEDURE - Step 23 [10/2022 - 10/2023] , or refer to PROCEDURE - Step 23 [10/2023 - ]

    3. Check the connections of the z27 battery ECU assembly connector.

      Refer to ELECTRONIC CIRCUIT INSPECTION PROCEDURE [11/2018 - ]

      OK

      The connector is connected securely and there are no contact problems.

      GTY975635Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Install the No. 1 HV battery hose.

      Result

      Result Proceed to
      OK A
      Not connected securely The terminals are not damaged or corroded B
      Not connected securely The terminals are damaged or corroded C

    Result: 

    CONNECT SECURELY 

    Result: 

    REPLACE NO. 2 HV SUPPLY STACK SUB-ASSEMBLY 

    Refer to REMOVAL [06/2020 - 08/2020] , or refer to REMOVAL [08/2020 - 12/2021] , or refer to REMOVAL [12/2021 - 10/2022] , or refer to REMOVAL [10/2022 - 10/2023] , or refer to REMOVAL [10/2023 - ]

    Result: 

    See step  4

  4. CHECK FREEZE FRAME DATA 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Enter the following menus: Powertrain / HV battery / Trouble Codes.
    4. Read the value of freeze frame data items "Hybrid/EV battery cell 36 voltage" through "Hybrid/EV battery cell 70 voltage" for DTC P1A00-1C and make a note if the value of any is 1.6 V or less.

      Powertrain > HV Battery > Trouble Codes 

    5. Turn the ignition switch off.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  5

  5. CHECK NO. 2 HV SUPPLY STACK SUB-ASSEMBLY (HYBRID BATTERY CELL VOLTAGE) 

    Refer to PROCEDURE - Step 7

    Result

    Result Proceed to
    The voltage between the terminals is 1.6 V or less. A
    Other than above B

    Result: 

    REPLACE NO. 2 HV SUPPLY STACK SUB-ASSEMBLY 

    Refer to REMOVAL [06/2020 - 08/2020] , or refer to REMOVAL [08/2020 - 12/2021] , or refer to REMOVAL [12/2021 - 10/2022] , or refer to REMOVAL [10/2022 - 10/2023] , or refer to REMOVAL [10/2023 - ]

    Result: 

    REPLACE BATTERY ECU ASSEMBLY 

    Refer to REMOVAL [06/2020 - 08/2020] , or refer to REMOVAL [08/2020 - 12/2021] , or refer to REMOVAL [12/2021 - 10/2022] , or refer to REMOVAL [10/2022 - 10/2023] , or refer to REMOVAL [10/2023 - ]

  6. CHECK CONNECTOR CONNECTION CONDITION (BATTERY ECU ASSEMBLY CONNECTOR) 
    WARNING:

    Be sure to wear insulated gloves and protective goggles.

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

      After removing the service plug grip, do not turn the ignition switch to ON (READY), unless instructed by the appropriate service information because this may cause a malfunction.

    2. Remove the No. 1 HV battery hose.

      Refer to PROCEDURE - Step 23 [06/2020 - 08/2020] , or refer to PROCEDURE - Step 23 [08/2020 - 12/2021] , or refer to PROCEDURE - Step 23 [12/2021 - 10/2022] , or refer to PROCEDURE - Step 23 [10/2022 - 10/2023] , or refer to PROCEDURE - Step 23 [10/2023 - ]

    3. Check the connections of the z29 battery ECU assembly connector.

      Refer to ELECTRONIC CIRCUIT INSPECTION PROCEDURE [11/2018 - ]

      OK

      The connector is connected securely and there are no contact problems.

      Result

      Result Proceed to
      OK A
      Not connected securely The terminals are not damaged or corroded B
      Not connected securely The terminals are damaged or corroded C
      GTY975263Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Install the No. 1 HV battery hose.

    Result: 

    CONNECT SECURELY 

    Result: 

    REPLACE NO. 1 HV SUPPLY STACK SUB-ASSEMBLY 

    Refer to REMOVAL [06/2020 - 08/2020] , or refer to REMOVAL [08/2020 - 12/2021] , or refer to REMOVAL [12/2021 - 10/2022] , or refer to REMOVAL [10/2022 - 10/2023] , or refer to REMOVAL [10/2023 - ]

    Result: 

    See step  7

  7. CHECK FREEZE FRAME DATA 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Enter the following menus: Powertrain / HV battery / Trouble Codes.
    4. Read the value of freeze frame data items "Hybrid/EV battery cell 1 voltage" through "Hybrid/EV battery cell 35 voltage" for DTC P301A-1C and make a note if the value of any is 1.6 V or less.

      Powertrain > HV Battery > Trouble Codes 

    5. Turn the ignition switch off.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  8

  8. CHECK NO. 1 HV SUPPLY STACK SUB-ASSEMBLY (HYBRID BATTERY CELL VOLTAGE) 

    Refer to PROCEDURE - Step 4

    Result

    Result Proceed to
    The voltage between the terminals is 1.6 V or less. A
    Other than above B

    Result: 

    REPLACE NO. 1 HV SUPPLY STACK SUB-ASSEMBLY 

    Refer to REMOVAL [06/2020 - 08/2020] , or refer to REMOVAL [08/2020 - 12/2021] , or refer to REMOVAL [12/2021 - 10/2022] , or refer to REMOVAL [10/2022 - 10/2023] , or refer to REMOVAL [10/2023 - ]

    Result: 

    REPLACE BATTERY ECU ASSEMBLY 

    Refer to REMOVAL [06/2020 - 08/2020] , or refer to REMOVAL [08/2020 - 12/2021] , or refer to REMOVAL [12/2021 - 10/2022] , or refer to REMOVAL [10/2022 - 10/2023] , or refer to REMOVAL [10/2023 - ]