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Fuel Pump Control Circuit [09/2014 - 10/2015]: Procedure

  1. PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE FUEL PUMP/SPEED) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Fuel Pump / Speed.
    5. Check whether operating sounds can be heard while operating the fuel pump using the Techstream.

      OK

      Operating sounds can be heard from fuel pump.

    Result:  NG

    NG 

    See step  6

    Result:  OK

    OK 

    See step  2

  2. PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE FUEL PUMP) 
    GTY294188Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the fuel tank assembly (See service information). Refer to REMOVAL [09/2014 - ] ).
    2. Remove the fuel pump from the fuel tank assembly.
    3. Clean the fuel pump to completely remove any remaining fuel.
    4. Connect the fuel pump connector.
      WARNING:

      Make sure that there is no fuel remaining inside or on the outside of the fuel pump.

    5. Connect the Techstream to the DLC3.
    6. Turn the power switch on (IG).
    7. Turn the Techstream on.
    8. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Fuel Pump Duty.
    9. Operate the fuel pump using the Active Test function and measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Techstream Operation Specified Condition
      1 - 2 FPC Duty: 25% 3.2 to 4.05 V
      FPC Duty: 80% 8.8 to 12.5 V
    10. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Fuel Pump/Speed.
    11. Operate the fuel pump using the Active Test function and measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Techstream Operation Specified Condition
      1 - 2 ON (FPC Duty: 90%) 9.0 to 14.0 V

      HINT: 

      • Be sure to measure the voltage with all the connectors connected.
      • Before performing this inspection, check that the auxiliary battery voltage is between 11 and 14 V (not depleted).
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Fuel Pump)

    Result:  NG

    NG 

    See step  7

    Result:  OK

    OK 

    See step  3

  3. INSPECT FUEL PUMP 
    1. Inspect the fuel pump (See service information). Refer to INSPECTION [09/2014 - ] ).

    Result:  OK

    OK 

    END 

    Result:  NG

    NG 

    See step  4

  4. REPLACE FUEL PUMP 
    1. Replace the fuel pump (See service information). Refer to REMOVAL [09/2014 - 09/2016] ).

      HINT: 

      Perform "Inspection After Repair" after replacing the fuel pump (See service information). Refer to INITIALIZATION [09/2014 - ] ).

    Result:  NEXT

    NEXT 

    See step  5

  5. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED 
    1. Check the fuel pump operation.

      OK

      Malfunction has been repaired successfully.

    Result:  OK

    OK 

    END 

    Result:  NG

    NG 

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [09/2014 - 10/2015] 

  6. INSPECT FUEL PUMP ECU (POWER SOURCE VOLTAGE) 
    GTY653049Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the fuel pump ECU connector.
    2. Turn the power switch on (IG).
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      U38-6 (+B) - U38-3 (E) Power switch on (IG) 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Fuel Pump ECU)

    Result:  NG

    NG 

    See step  11

    Result:  OK

    OK 

    See step  7

  7. INSPECT FUEL PUMP 
    1. Inspect the fuel pump.

      Refer to INSPECTION [09/2014 - ]

      HINT: 

      Perform "Inspection After Repair" after replacing the fuel pump.

      Refer to INITIALIZATION [09/2014 - ]

    Result:  NG

    NG 

    REPLACE FUEL PUMP 

    (See service information). Refer to REMOVAL [09/2014 - 09/2016] )

    Result:  OK

    OK 

    See step  8

  8. CHECK HARNESS AND CONNECTOR (FUEL PUMP - FUEL PUMP ECU) 
    1. Disconnect the fuel pump connector.
    2. Disconnect the fuel pump ECU connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      U11-4 (B) - U38-1 (FP) Always Below 1 Ω
      U11-5 (E) - U38-2 (FP-) Always Below 1 Ω
      U11-4 (B) or U38-1 (FP) - Body ground Always 10 kΩ or higher
      U11-5 (E) or U38-2 (FP-) - Body ground Always 10 kΩ or higher

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  9

  9. CHECK HARNESS AND CONNECTOR (FUEL PUMP ECU - ECM) 
    1. Disconnect the fuel pump ECU connector.
    2. Disconnect the ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      U38-5 (FPC) - A20-18 (FPC) Always Below 1 Ω
      U38-5 (FPC) or A20-18 (FPC) - Body ground Always 10 kΩ or higher

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  10

  10. INSPECT ECM (FPC TERMINAL) 
    1. Disconnect the fuel pump ECU connector.
      GTY653050Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Connect the Techstream to the DLC3.
    3. Turn the power switch on (IG).
    4. Turn the Techstream on.
    5. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Fuel Pump / Speed.
    6. Operate the fuel pump control ECU assembly using the Active Test function and measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection GTS Operation Specified Condition
      U38-5 (FPC) - Body ground Before Active Test → During Active Test Before Active Test: Resistance is stable → During Active Test: Resistance fluctuates*

      HINT: 

      *: Using the Active Test, duty control of the transistors in the ECM will be performed. Due to the duty control, resistance of the FPC terminal will be unstable during the Active Test. If the resistance is stable before the Active Test and fluctuates while performing the Active Test, it can be determined that the transistor is operating. If the transistor does not operate during the Active Test, the ECM may be malfunctioning.

      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Fuel Pump ECU)

    Result:  OK

    OK 

    REPLACE FUEL PUMP ECU 

    (See service information). Refer to REMOVAL [09/2014 - 10/2015] )

    Result:  NG

    NG 

    REPLACE ECM 

    (See service information). Refer to REMOVAL [09/2014 - ] )

  11. CHECK HARNESS AND CONNECTOR (FUEL PUMP ECU - BODY GROUND) 
    1. Disconnect the fuel pump ECU connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      U38-3 (E) - Body ground Always Below 1 Ω

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  12

  12. CHECK HARNESS AND CONNECTOR (EFI MAIN2 RELAY - FUEL PUMP ECU) 
    1. Remove the No. 1 integration relay from the No. 1 engine room relay block and junction block assembly.
    2. Disconnect the fuel pump ECU connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      1F-12 - U38-6 (+B) Always Below 1 Ω
      1F-12 or U38-6 (+B) - Body ground Always 10 kΩ or higher

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  13

  13. INSPECT NO. 1 INTEGRATION RELAY (EFI MAIN2) 
    1. Inspect the No. 1 integration relay (EFI MAIN2) (See service information). Refer to PROCEDURE - Step 2 ).

    Result:  OK

    OK 

    GO TO ECM POWER SOURCE CIRCUIT 

    (See service information). Refer to ECM Power Source Circuit [09/2014 - ] )

    Result:  NG

    NG 

    REPLACE NO. 1 INTEGRATION RELAY 

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