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Fuel System: Precaution

CAUTION:
  • Before working on the fuel system, disconnect the cable from the negative (-) battery terminal and remove the service plug grip.
  • Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to prevent airbag and seat belt pretensioner activation.
  • Do not smoke or be near an open flame when working on the fuel system.
  • Keep gasoline away from rubber or leather parts.
  • Do not allow fuel to spray when removing the pipe between the high pressure side fuel pump and the fuel injector. The fuel in the pipe is highly pressurized.
  1. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL 
    CAUTION: Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to prevent airbag and seat belt pretensioner activation.
    NOTE:
    • When disconnecting the cable, some systems need to be initialized after the cable is reconnected (see INITIALIZATION ).
    • After the power switch is turned OFF, the HDD navigation system requires approximately 6 minutes to record various types of memory and settings. As a result, after turning the power switch OFF, wait 6 minutes or more before disconnecting the cable from the negative (-) battery terminal.
  2. DISCHARGE FUEL SYSTEM PRESSURE 
    CAUTION:
    • Do not disconnect any part of the fuel system until you have discharged the fuel system pressure.
    • Even after discharging the fuel pressure, place a piece of cloth or equivalent over fittings as you separate them to reduce the risk of fuel spray on yourself or in the engine compartment.
    • Allow the engine to cool down before performing the following procedures, as the high pressure side's fuel pressure does not decrease until the engine cools down.
    NOTE: Perform these procedures with the engine coolant temperature at 60C (140°F) or less.
    1. for Circuit Opening Relay (C/OPN).
      1. Remove the engine room side cover RH.
      2. Remove the engine room No 2 relay block cover.
      3. Remove the circuit opening relay.
      4. Fig 1: Identifying Circuit Opening Relay
        G05772825Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      5. Put the engine in inspection mode (see INSPECTION MODE PROCEDURE ).
      6. Start the engine.
      7. After the engine has stopped on its own, turn the power switch OFF.

        HINT:

        DTC P3190 and/or P3191 may be set.

      8. Try to start the engine again, then check that the engine does not start.
      9. Loosen the fuel tank cap, then discharge the pressure in the fuel tank completely.
      10. Disconnect cable from negative (-) battery terminal.
      11. Install the circuit opening relay.
      12. Install the engine room No. 2 relay block cover.
      13. Install the engine room side cover RH.
    2. for Fuel Pump Connector:
      1. for Power Seat:

        Remove the rear No. 2 seat adjuster assembly (see REMOVAL ).

      2. for Ottoman:

        Remove the rear No. 2 seat adjuster assembly (see REMOVAL ).

      3. for Fixed Seat Type:

        Remove the rear seat cushion assembly (see REMOVAL ).

      4. Disconnect the fuel pump connector.
      5. Fig 2: Locating Fuel Pump Connector
        G05772826Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      6. Put the engine in inspection mode (see INSPECTION MODE PROCEDURE ).
      7. Start the engine.
      8. After the engine has stopped on its own, turn the power switch OFF

        HINT:

        DTC P3190 and/or P3191 may be set.

      9. Try to start the engine again, then check that the engine does not start.
      10. Loosen the fuel tank cap, then discharge the pressure in the fuel tank completely.
      11. Disconnect cable from negative (-) battery terminal.
      12. Connect the fuel pump connector.
      13. for Power Seat:

        Install rear No. 2 seat adjuster assembly (see INSTALLATION ).

      14. for Ottoman:

        Install rear No. 2 seat adjuster assembly (see INSTALLATION )

      15. for Fixed Seat Type:

        Install the rear seat cushion assembly (see INSTALLATION ).

  3. FUEL SYSTEM 
    1. When disconnecting the fuel pressure line, a large amount of gasoline will spill out. Follow the following procedures:
      1. Discharge the fuel system pressure.
      2. Put a container under the connection.
      3. Disconnect the fuel pump tube.
      4. Drain the fuel remaining inside the fuel pump tube into the container
      5. To protect the disconnected fuel pump tube from damage and contamination, cover it with a plastic bag.
        Fig 3: Identifying Fuel Pump Tube In Plastic Bag
        G05772827Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Observe the following precautions when disconnecting the fuel tube connector (for quick type A).
      1. for Fuel Pipe Clamp Type: Remove the fuel pipe clamp.
        Fig 4: Locating Fuel Tube Connector
        G04947837Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. for Retainer Type:

        Pull up the retainer to release the lock.

        Fig 5: Pulling Retainer
        G04947838Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Check for foreign matter on the pipe and around the connector before disconnecting it. Clean it if necessary.
      4. Pinch the connector and disconnect the connector and pipe

        HINT:

        If the connector and pipe are stuck, pinch the connector, and push and pull the pipe to disconnect them.

        NOTE: Do not use any tools in this procedure.
        Fig 6: Pinching Connector And Pipe
        G05772830Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      5. Check for foreign matter on the seal surface of the disconnected pipe. Clean it if necessary.
      6. To protect the disconnected pipe and connector from damage and foreign matter, cover it with a plastic bag
        Fig 7: Identifying Connector In Plastic Bag
        G04947840Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Observe the following precautions when connecting the fuel tube connector (for quick type A):
      1. Check that there is no damage or foreign matter on the part of the pipe that contacts the connector.
      2. Align the axis of the connector with the axis of the pipe. Push the pipe into the connector until the connector makes a "click" sound If the connection is too tight, apply a light coat of fresh engine oil to the tip of the pipe.
        Fig 8: Pushing Pipe Into Connector
        G05772832Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. After connecting the pipe and connector, try to pull them apart to confirm that they are securely connected
    4. for Fuel Pipe Clamp Type:

      Install the fuel pipe clamp

    5. for Retainer Type.

      Push down the retainer to lock it

      Fig 9: Pulling Pipe Into Connector
      G04947842Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    6. Observe the following precautions when disconnecting the fuel tube connector (for quick type B):
      1. Check that there is no damage or foreign matter on the part of the pipe that contacts the connector.
        Fig 10: Checking Fuel Tube Connector Retainer
        G05628776Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Detach the 2 claws of the connector retainer. Push down on the connector and disconnect it from the pipe.

        HINT.

        If the connector and pipe are stuck, pinch the fuel pipe by hand, and push and pull the connector to disconnect it

        NOTE: Do not use any tools in this procedure.
        Fig 11: Detaching Claws Of Connector Retainer
        G04947844Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Check for foreign matter on the seal surface of the disconnected pipe Clean it if necessary.
      4. To protect the disconnected pipe and connector from damage and foreign matter, cover it with a plastic bag
        Fig 12: Identifying Connector In Plastic Bag
        G05628778Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    7. Observe the following precautions when connecting the fuel tube connector (for quick type B).
      1. Check for foreign matter on the pipe and around the connector before connecting it. Clean it if necessary.
      2. Align the axis of the connector with the axis of the pipe Push the pipe into the connector, and push up on the retainer.
        Fig 13: Pushing Pipe Into Connector
        G04947846Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. After connecting the pipe and connector, try to pull them apart to confirm that they are securely connected.
  4. CHECK FOR FUEL LEAK 
    1. Check that there are no fuel leaks anywhere on the fuel system after performing maintenance (see ON-VEHICLE INSPECTION  ).
      Fig 14: Checking Connector Connection
      G04947847Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002