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Battery Ecu ASSY: Replacement

WARNING: This page is about a different car, the 2004 Toyota Prius. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
  • When working on the high voltage systems, always wear insulating gloves.
  • After removing the service plug grip, do not operate the power switch as it may damage the hybrid vehicle control ECU.
  • Keep the removed service plug in your pocket to prevent other technicians from reconnecting it while you are servicing the vehicle.
  • After removing the service plug grip, do not touch the high voltage connectors and terminals for 5 minutes.
  1. PRECAUTION (See  PRECAUTION  ) 
  2. REMOVE REAR FLOOR BOARD NO. 2 (See  SERVICE PLUG GRIP  ) 
  3. REMOVE DECK FLOOR BOX REAR (See  SERVICE PLUG GRIP  ) 
  4. REMOVE REAR FLOOR BOARD NO. 3 (See  SERVICE PLUG GRIP  ) 
  5. DISCONNECT BATTERY NEGATIVE TERMINAL (See  SERVICE PLUG GRIP  ) 
  6. REMOVE SERVICE PLUG GRIP (See  SERVICE PLUG GRIP  ) 
  7. REMOVE DECK TRIM COVER REAR (See  REMOVAL & INSTALLATION AND DISASSEMBLY & REASSEMBLY  ) 
  8. REMOVE TONNEAU COVER ASSY (See  REMOVAL & INSTALLATION AND DISASSEMBLY & REASSEMBLY  ) 
  9. REMOVE REAR SEAT CUSHION ASSY (See  REMOVAL & INSTALLATION AND DISASSEMBLY & REASSEMBLY  ) 
  10. REMOVE REAR FLOOR BOARD NO. 1 (See  REMOVAL & INSTALLATION AND DISASSEMBLY & REASSEMBLY  ) 
  11. REMOVE REAR SIDE SEAT BACK FRAME LH (See  REMOVAL & INSTALLATION AND DISASSEMBLY & REASSEMBLY  ) 
  12. REMOVE REAR FLOOR BOARD NO. 4 (See  REMOVAL & INSTALLATION AND DISASSEMBLY & REASSEMBLY  ) 
  13. REMOVE DECK FLOOR BOX LH (See  REMOVAL & INSTALLATION AND DISASSEMBLY & REASSEMBLY  ) 
  14. REMOVE DECK TRIM SIDE PANEL ASSY LH (See  REMOVAL & INSTALLATION AND DISASSEMBLY & REASSEMBLY  ) 
  15. REMOVE BATTERY CARRIER BRACKET (See  REMOVAL & INSTALLATION AND DISASSEMBLY & REASSEMBLY  ) 
  16. REMOVE BATTERY CARRIER PANEL NO. 6 (See  REMOVAL & INSTALLATION AND DISASSEMBLY & REASSEMBLY  ) 
    NOTE: Wear insulating gloves.
  17. REMOVE JUNCTION TERMINAL (See  REMOVAL & INSTALLATION AND DISASSEMBLY & REASSEMBLY  ) 
    NOTE: Wear insulating gloves.
  18. REMOVE BATTERY ECU ASSY 
    NOTE: Wear insulating gloves.
    1. Disconnect the system main relay connector.
      NOTE: Insulate the disconnected connectors with insulating tape.
    2. Disconnect the battery ECU assembly connector.
      NOTE: Insulate the disconnected connectors with insulating tape.
      Fig 1: Disconnecting System Main Relay Connector, Battery ECU Assembly Connector & Thermistor Connector
      G00950507Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Disconnect the thermistor connector.
      NOTE: Insulate the disconnected connectors with insulating tape.
    4. Remove the clamp, then disconnect the frame wire No. 2 connector.
      NOTE: Insulate the disconnected connectors with insulating tape.
    5. Remove the nut, then disconnect the aluminum shield wire of the main battery cable.
    6. Remove the 2 screws and battery ECU assembly.
      Fig 2: Removing Battery ECU Assembly
      G00950508Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  19. INSTALL BATTERY ECU ASSY 
    NOTE: Wear insulating gloves.
    1. Install the battery ECU assembly with the 2 screws.

      Torque: 3.3 N.m (34 kgf.cm, 29 in.lbf) 

    2. Tighten the aluminum shield wire of the main battery cable together with the battery ECU assembly with a new nut.

      Torque: 3.3 N.m (34 kgf.cm, 29 in.lbf) 

    3. Connect the clamp and frame wire No. 2 connector.
    4. Connect the thermistor connector.
      Fig 3: Connecting Thermistor Connector
      G00950509Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Connect the system main relay connector.
    6. Remove the 2 screws and battery ECU assembly.
      Fig 4: Connecting System Main Relay Connector
      G00950510Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  20. INSTALL JUNCTION TERMINAL (See  REMOVAL & INSTALLATION AND DISASSEMBLY & REASSEMBLY  ) 
    NOTE: Wear insulating gloves.
  21. INSTALL BATTERY CARRIER PANEL NO. 6 (See  REMOVAL & INSTALLATION AND DISASSEMBLY & REASSEMBLY  ) 
    NOTE: Wear insulating gloves.
  22. INSTALL BATTERY CARRIER BRACKET (See  REMOVAL & INSTALLATION AND DISASSEMBLY & REASSEMBLY  ) 
  23. INSTALL DECK TRIM SIDE PANEL ASSY LH 
  24. INSTALL DECK FLOOR BOX LH 
  25. INSTALL REAR FLOOR BOARD NO. 4 
  26. INSTALL REAR SIDE SEAT BACK FRAME LH 
  27. INSTALL REAR FLOOR BOARD NO. 1 
  28. INSTALL REAR SEAT CUSHION ASSY 
  29. INSTALL TONNEAU COVER ASSY 
  30. INSTALL DECK TRIM COVER REAR 
  31. INSTALL SERVICE PLUG GRIP (See  SERVICE PLUG GRIP  ) 
    NOTE: Wear insulating gloves.
  32. CONNECT BATTERY NEGATIVE TERMINAL 

    Torque: 6.0 N.m (61 kgf.cm, 53 in.lbf) 

  33. INSTALL REAR FLOOR BOARD NO. 3 
  34. INSTALL DECK FLOOR BOX REAR 
  35. INSTALL REAR FLOOR BOARD NO. 2 
  36. POWER WINDOW CONTROL SYSTEM INITIALIZE (See  INITIALIZATION  ) 
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