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System Main Relay No. 1: 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  ) 
  17. REMOVE JUNCTION TERMINAL (See  REMOVAL & INSTALLATION AND DISASSEMBLY & REASSEMBLY  ) 
    NOTE: Wear insulating gloves.
  18. SEPARATE FRAME WIRE (See  REMOVAL & INSTALLATION AND DISASSEMBLY & REASSEMBLY  ) 
    NOTE: Wear insulating gloves.
  19. REMOVE SYSTEM MAIN RELAY NO. 2 (See  SYSTEM MAIN RELAY NO. 2  ) 
    NOTE: Wear insulating gloves.
  20. REMOVE SYSTEM MAIN RELAY NO. 3 (See  SYSTEM MAIN RELAY NO. 3  ) 
    NOTE: Wear insulating gloves.
  21. REMOVE SYSTEM MAIN RELAY NO. 1 
    NOTE: Wear insulating gloves.
    1. Disconnect the connector.
    2. Remove the nut, then disconnect the ground terminal.
    3. Disconnect the 2 clamps.
    4. Remove the system main relay connector.
    5. Remove the 2 bolts and system main relay No. 1.
      Fig 1: Removing System Main Relay No. 1
      G00950486Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  22. INSTALL SYSTEM MAIN RELAY NO. 1 
    NOTE: Wear insulating gloves.
    1. Install the system main relay No. 1 with the 2 bolts.

      Torque: 3.4 N.m (35 kgf.cm, 30 in.lbf) 

    2. Connect the system main relay connector.
    3. Connect the 2 clamps, then install the system main relay sub wiring harness to the upper battery carrier.
    4. Install the ground terminal with the nut.

      Torque: 5.6 N.m (57 kgf.cm, 50 in.lbf) 

    5. Install the connector.
      Fig 2: Installing System Main Relay No. 1
      G00950487Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  23. INSTALL SYSTEM MAIN RELAY NO. 3 (See  SYSTEM MAIN RELAY NO. 3  ) 
    NOTE: Wear insulating gloves.
  24. INSTALL SYSTEM MAIN RELAY NO. 2 (See  SYSTEM MAIN RELAY NO. 2  ) 
    NOTE: Wear insulating gloves.
  25. INSPECT CONTACT CONDITION 
    NOTE: Wear insulating gloves.
    1. Check that all the wiring wire harnesses are correctly and securely connected on the upper battery carrier.
      Fig 3: Locating Wiring Wire Harnesses On Upper Battery Carrier
      G00950488Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      NOTE: Make sure that the connectors and clamps are connected exactly the same as the illustration above. If any of them is different, correct it immediately.
  26. INSTALL FRAME WIRE (See  REMOVAL & INSTALLATION AND DISASSEMBLY & REASSEMBLY  ) 
    NOTE: Wear insulating gloves.
  27. INSTALL JUNCTION TERMINAL (See  REMOVAL & INSTALLATION AND DISASSEMBLY & REASSEMBLY  ) 
    NOTE: Wear insulating gloves.
  28. INSTALL BATTERY CARRIER PANEL NO. 6 (See  REMOVAL & INSTALLATION AND DISASSEMBLY & REASSEMBLY  ) 
  29. INSTALL BATTERY CARRIER BRACKET (See  REMOVAL & INSTALLATION AND DISASSEMBLY & REASSEMBLY  ) 
  30. INSTALL DECK TRIM SIDE PANEL ASSY LH 
  31. INSTALL DECK FLOOR BOX LH 
  32. INSTALL REAR FLOOR BOARD NO. 4 
  33. INSTALL REAR SIDE SEAT BACK FRAME LH 
  34. INSTALL REAR FLOOR BOARD NO. 1 
  35. INSTALL REAR SEAT CUSHION ASSY 
  36. INSTALL TONNEAU COVER ASSY 
  37. INSTALL DECK TRIM COVER REAR 
  38. INSTALL SERVICE PLUG GRIP (See  SERVICE PLUG GRIP  ) 
    NOTE: Wear insulating gloves.
  39. CONNECT BATTERY NEGATIVE TERMINAL 

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

  40. INSTALL REAR FLOOR BOARD NO. 3 
  41. INSTALL DECK FLOOR BOX REAR 
  42. INSTALL REAR FLOOR BOARD NO. 2 
  43. POWER WINDOW CONTROL SYSTEM INITIALIZE (See  INITIALIZATION  ) 
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