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Removal [11/2021 - ]: Procedure

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  1. PRECAUTION 
    NOTE:

    After the ignition switch is turned off, there may be a waiting time before disconnecting the negative (-) auxiliary battery terminal.

    Refer to BEFORE DISCONNECTING BATTERY [11/2021 - ]

    Refer to PRECAUTION [11/2021 - ]

  2. WHEN REPLACING BATTERY ECU ASSEMBLY 
    NOTE:
    • Do not replace the battery ECU assembly and ECM at the same time as the HV battery learning values will be lost. However, if it is necessary to replace both ECUs at the same time, replace them by following the procedure below.
    • Do not replace the battery ECU assembly or ECM with a used one from another vehicle.

    HV battery learning values are stored in the battery ECU assembly and ECM and are used to detect malfunctions and illuminate the hybrid battery indicator light in the combination meter assembly. When either of these ECUs is replaced, the new ECU receives the HV battery learning values from the other ECU and stores them.

    1. Procedure when replacing both battery ECU assembly and ECM:
      1. Disconnect the cable from the negative (-) auxiliary battery terminal.
      2. Replace either ECU.
      3. Connect the cable to the negative (-) auxiliary battery terminal.
      4. Turn the ignition switch to on (READY) and wait for 5 minutes or more.
      5. Turn the ignition switch off and disconnect the cable from the negative (-) auxiliary battery terminal.
      6. Replace the other ECU.
      7. Connect the cable to the negative (-) auxiliary battery terminal.
      8. Check that the ignition switch can be turned to on (READY).

        HINT: 

        If the battery ECU assembly and ECM are replaced at the same time without following the above procedure, replace either of the ECUs with its original one and then replace it again by following the above procedure. If the correct procedure is not followed, perform the procedure again from the beginning.

  3. REMOVE SERVICE PLUG GRIP 

    Refer to PROCEDURE - Step 5

  4. REMOVE NO. 2 INVERTER PROTECTOR 

    See step  8

  5. DISCONNECT ENGINE ROOM MAIN WIRE 
    Refer to PROCEDURE - Step 4
  6. REMOVE CONNECTOR COVER ASSEMBLY 
    See step  10
  7. CHECK TERMINAL VOLTAGE 
    See step  11
  8. INSTALL CONNECTOR COVER ASSEMBLY 
    See step  8
  9. CONNECT ENGINE ROOM MAIN WIRE 
    Refer to PROCEDURE - Step 31
  10. INSTALL NO. 2 INVERTER PROTECTOR 

    See step  18

  11. REMOVE NO. 2 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY 

    Refer to REMOVAL [11/2021 - ]

  12. REMOVE REAR DOOR SCUFF PLATE LH 

    Refer to PROCEDURE - Step 21

  13. REMOVE NO. 3 BATTERY SERVICE COVER BOARD 

    Refer to PROCEDURE - Step 23

  14. REMOVE REAR DOOR SCUFF PLATE RH 
    1. Use the same procedure as for the LH side.
  15. REMOVE NO. 2 BATTERY SERVICE COVER BOARD 
    1. Use the same procedure as for the No. 3 battery service cover board.
  16. REMOVE BATTERY SERVICE COVER BOARD 

    Refer to PROCEDURE - Step 7

  17. REMOVE REAR SEAT CUSHION LEG SUB-ASSEMBLY 

    Refer to PROCEDURE - Step 8

  18. REMOVE NO. 1 HV BATTERY COVER PANEL RH 
    See step  12
  19. REMOVE HYBRID BATTERY HOSE ASSEMBLY 

    See step  15

  20. DISCONNECT FLOOR WIRE 
    See step  17
  21. REMOVE NO. 4 HV BATTERY PROTECTOR 
    See step  18
  22. DISCONNECT FLOOR WIRE 
    See step  19
  23. REMOVE UPPER HV BATTERY COVER SUB-ASSEMBLY 
    WARNING:

    Be sure to wear insulated gloves and protective goggles.
    1. GTY1066020Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  24. REMOVE NO. 1 HV BATTERY HOSE 
    WARNING:

    Be sure to wear insulated gloves and protective goggles.
    1. GTY999802Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. GTY1074146Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      Remove in this Direction (1) Remove in this Direction (2)
  25. REMOVE BATTERY ECU ASSEMBLY 
    WARNING:

    Be sure to wear insulated gloves and protective goggles.
    1. GTY1080451Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Disengage the clamp.
      2. Move the lock lever while pushing the lock, and disconnect the 3 battery ECU assembly connectors.
        NOTE:
        • Make sure to release the lock of the lock lever before moving it.
          GTY737421Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
          *a Lever Lock
        • If the connector cannot be disconnected, check if the lock lever is completely unlocked.
        • Insulate each disconnected high-voltage connector with insulating tape. Wrap the connector from the wire harness side to the end of the connector.
      3. Remove the 3 nuts and battery ECU assembly from the HV battery.
        NOTE:

        If the battery ECU assembly has been struck or dropped, replace it.

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