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Fuel Pump Control Circuit [09/2015 - ]: Procedure

  1. CHECK FUEL PUMP OPERATION 
    1. Check the fuel pressure (Refer to PROCEDURE - Step 2 ).

      HINT: 

      If there is fuel pressure, you will hear the sound of fuel flowing.

    Result:  OK

    OK 

    See step  10

    Result:  NG

    NG 

    See step  2

  2. PERFORM ACTIVE TEST USING TECHSTREAM (OPERATE CIRCUIT OPENING RELAY (C/OPN) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG) and turn the Techstream on.
    3. Enter the following menus: Powertrain / Engine / Active Test / Control the Fuel Pump / Speed
    4. Check whether operating sounds can be heard while operating the relay using the Techstream.

      OK

      Operating sounds can be heard from relay.

    Result:  OK

    OK 

    See step  5

    Result:  NG

    NG 

    See step  3

  3. INSPECT CIRCUIT OPENING RELAY (C/OPN) 
    GTY141650Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the C/OPN relay from the engine room No. 2 relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection Condition Specified Condition
      3 - 5 When no battery voltage applied to terminals 1 and 2 10 kΩ or higher
      3 - 5 When battery voltage applied to terminals 1 and 2 Below 1 Ω

    Result:  NG

    NG 

    REPLACE CIRCUIT OPENING RELAY (C/OPN) 

    Result:  OK

    OK 

    See step  4

  4. INSPECT ECM (FC VOLTAGE) 
    GTY648861Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Turn the engine switch on (IG).
    2. Measure the voltage according to the value(s) in the table below.

      Standard voltage

      Tester Connection Switch Condition Specified Condition
      A14-5 (FC) - E3-1 (E1) Engine switch on (IG) 11 to 14 V

    Result:  NG

    NG 

    CHECK AND REPLACE HARNESS OR CONNECTOR (CIRCUIT OPENING RELAY (C/OPN) - ECM, EFI-B FUSE) 

    Result:  OK

    OK 

    REPLACE ECM 

    (Refer to REMOVAL [09/2015 - ] )

  5. INSPECT ECM POWER SOURCE CIRCUIT 
    1. Inspect the ECM power source circuit (Refer to ECM Power Source Circuit [09/2015 - ] ).

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  6

  6. INSPECT FUEL PUMP RELAY (F/PMP) 

    Refer to PROCEDURE - Step 2

    Result:  NG

    NG 

    REPLACE FUEL PUMP RELAY (F/PMP) 

    Result:  OK

    OK 

    See step  7

  7. INSPECT FUEL PUMP 
    GTY285155Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Inspect the fuel pump resistance.
      1. Measure the resistance according to the value(s) in the table below.

        Standard resistance

        Tester Connection Condition Specified Condition
        4 - 5 20°C (68°F) 0.2 to 3.0 Ω
    2. Inspect the fuel pump operation.
      1. Apply battery voltage to both terminals. Check that the pump operates.
        NOTE:
        • These tests must be done quickly (within 10 seconds) to prevent the coil from burning out.
        • Keep the fuel pump as far away from the battery as possible.
        • Always turn the voltage on and off on the battery side, not the fuel pump side.

        HINT: 

        Perform "Inspection After Repair" after replacing the fuel pump (Refer to INITIALIZATION [09/2015 - ] ).

    Result:  NG

    NG 

    REPLACE FUEL PUMP 

    (Refer to REMOVAL [09/2015 - ] )

    Result:  OK

    OK 

    See step  8

  8. CHECK HARNESS AND CONNECTOR (FUEL PUMP - FUEL PUMP RELAY (F/PMP), BODY GROUND) 
    GTY648394Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Check the harness and connector between the fuel pump and F/PMP relay.
      1. Disconnect the S11 fuel pump connector.
      2. Remove the F/PMP relay from the engine room No. 2 relay block.
      3. Measure the resistance according to the value(s) in the table below.

        Standard resistance (Check for open)

        Tester Connection Condition Specified Condition
        S11-4 - F/PMP relay (3) Always Below 1 Ω

        Standard resistance (Check for short)

        Tester Connection Condition Specified Condition
        S11-4 or F/PMP relay (3) - Body ground Always 10 kΩ or higher
      4. Reconnect the fuel pump connector.
      5. Reinstall the F/PMP relay.
    2. Check the harness and connector between the fuel pump and body ground.
      1. Disconnect the S11 fuel pump connector.
      2. Measure the resistance according to the value(s) in the table below.

        Standard resistance (Check for open)

        Tester Connection Condition Specified Condition
        S11-5 - Body ground Always Below 1 Ω
      3. Reconnect the fuel pump connector.

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  9

  9. CHECK HARNESS AND CONNECTOR (CIRCUIT OPENING RELAY (C/OPN) - FUEL PUMP RELAY (F/PMP) 
    GTY462216Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the C/OPN relay and F/PMP relay from the engine room No. 2 relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance (Check for open)

      Tester Connection Condition Specified Condition
      C/OPN relay (3) - F/PMP relay (4) Always Below 1 Ω

      Standard resistance (Check for short)

      Tester Connection Condition Specified Condition
      C/OPN relay (3) or F/PMP relay (4) - Body ground Always 10 kΩ or higher

    Result:  OK

    OK 

    CHECK AND REPAIR HARNESS OR CONNECTOR (EFI RELAY (EFI MAIN) - CIRCUIT OPENING RELAY (C/OPN) 

    Result:  NG

    NG 

    REPAIR OR REPLACE ENGINE ROOM NO. 2 RELAY BLOCK, JUNCTION BLOCK 

  10. INSPECT FUEL PUMP RELAY (F/PMP) 

    Refer to PROCEDURE - Step 2

    Result:  NG

    NG 

    REPLACE FUEL PUMP RELAY (F/PMP) 

    Result:  OK

    OK 

    See step  11

  11. INSPECT FUEL PUMP RESISTOR (RESISTANCE) 
    GTY612028Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Inspect the fuel pump resistor resistance.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection Condition Specified Condition
      1 - 2 20°C (68°F) 0.941 to 0.999 Ω

    Result:  NG

    NG 

    REPLACE FUEL PUMP RESISTOR 

    (Refer to REMOVAL [09/2015 - ] )

    Result:  OK

    OK 

    See step  12

  12. CHECK HARNESS AND CONNECTOR (FUEL PUMP RESISTOR - FUEL PUMP RELAY (F/PMP) 
    GTY643399Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the F/PMP relay from the engine room No. 2 relay block.
    2. Disconnect the A16 fuel pump resistor connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance (Check for open)

      Tester Connection Condition Specified Condition
      F/PMP relay (4) - A16-1 Always Below 1 Ω

      Standard resistance (Check for short)

      Tester Connection Condition Specified Condition
      F/PMP relay (4) or A16-1 - Body ground Always 10 kΩ or higher
    4. Reinstall the F/PMP relay.
    5. Reconnect the fuel pump resistor connector.

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  13

  13. CHECK HARNESS AND CONNECTOR (FUEL PUMP RESISTOR - FUEL PUMP) 
    GTY650072Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A16 fuel pump resistor connector.
    2. Disconnect the S11 fuel pump connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance (Check for open)

      Tester Connection Condition Specified Condition
      A16-2 - S11-4 Always Below 1 Ω

      Standard resistance (Check for short)

      Tester Connection Condition Specified Condition
      A16-2 or S11-4 - Body ground Always 10 kΩ or higher
    4. Reconnect the fuel pump resistor connector.
    5. Reconnect the fuel pump connector.

    Result:  OK

    OK 

    PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE 

    (Refer to PROBLEM SYMPTOMS TABLE [09/2015 - ] )

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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