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

  1. CHECK VEHICLE SPECIFICATION 
    1. Check the type of motor of the fuel pump (for low pressure side).
      1. Check that the Active Test item "Fuel Pump Single Phase Energization" is displayed.
        • If the fuel pump (for low pressure side) is a brush type motor, the Active Test item "Fuel Pump Single Phase Energization" will not be displayed.
        • If the fuel pump (for low pressure side) is a brushless type motor, the Active Test item "Fuel Pump Single Phase Energization" will be displayed.

      Result

      Result Proceed to
      for fuel pump (for low pressure side) (brush Type motor) A
      for fuel pump (for low pressure side) (brushless Type motor) B

    Result: 

    B 

    See step  18

    Result: 

    A 

    See step  2

  2. PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE FUEL PUMP/SPEED) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine / Active Test / Control the Fuel Pump/Speed.

      Powertrain > Engine > Active Test 

      Tester Display
      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 the fuel pump.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  5

    Result: 

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (ECM - FUEL PUMP CONTROL ECU - FUEL PUMP (FOR LOW PRESSURE SIDE)) 
    1. Disconnect the ECM connector.
    2. Disconnect the fuel pump control ECU connector.
    3. Disconnect the fuel pump (for low pressure side) connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A77-17 (FPC) - U27-1 (FPC) Always Below 1 Ω
      U29-1 (FP) - U25-4 (B2) Always Below 1 Ω
      U29-2 (FP-) - U25-5 (E2) Always Below 1 Ω
      A77-17 (FPC) or U27-1 (FPC) - Body ground Always 10 kΩ or higher
      U29-1 (FP) or U25-4 (B2) - Body ground Always 10 kΩ or higher
      U29-2 (FP-) or U25-5 (E2) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  4

  4. REPLACE FUEL PUMP CONTROL ECU 
    1. Replace the fuel pump control ECU.

      Refer to REMOVAL [09/2014 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  11

  5. INSPECT FUEL PUMP CONTROL ECU (POWER SOURCE VOLTAGE) 
    GTY511220Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Front view of wire harness connector
    (to Fuel Pump Control ECU)
    1. Disconnect the fuel pump control ECU connector.
    2. Turn the engine switch on (IG).
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      U27-4 (+B) - Body Ground Engine switch on (IG) 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  12

    Result: 

    OK 

    See step  6

  6. CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU - FUEL PUMP (FOR LOW PRESSURE SIDE)) 
    1. Disconnect the fuel pump control ECU connector.
    2. Disconnect the fuel pump (for low pressure side) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      U29-1 (FP) - U25-4 (B2) Always Below 1 Ω
      U29-2 (FP-) - U25-5 (E2) Always Below 1 Ω
      U29-1 (FP) or U25-4 (B2) - Body ground Always 10 kΩ or higher
      U29-2 (FP-) or U25-5 (E2) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  7

  7. INSPECT FUEL PUMP (FOR LOW PRESSURE SIDE) 
    1. Inspect the fuel pump (for low pressure side).

      Refer to INSPECTION [09/2014 - ]

      HINT: 

      Perform "Inspection After Repair" after replacing the fuel pump (for low pressure side).

      Refer to INITIALIZATION [09/2014 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE FUEL PUMP (FOR LOW PRESSURE SIDE). Refer to  REMOVAL [09/2014 - ] 

    Result: 

    OK 

    See step  8

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      U27-3 (E) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  9

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      A77-17 (FPC) - U27-1 (FPC) Always Below 1 Ω
      A77-14 (DI) - U27-2 (DI) Always Below 1 Ω
      A77-17 (FPC) or U27-1 (FPC) - Body ground Always 10 kΩ or higher
      A77-14 (DI) or U27-2 (DI) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  10

  10. REPLACE FUEL PUMP CONTROL ECU 
    1. Replace the fuel pump control ECU.

      Refer to REMOVAL [09/2014 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  11

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

      Refer to PROCEDURE - Step 1

      OK

      Malfunction has been repaired successfully.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END 

    Result: 

    NG 

    REPLACE ECM. Refer to  REMOVAL [09/2014 - ] 

  12. INSPECT RELAY (C/OPN) 
    1. Inspect the C/OPN relay.

      Refer to PROCEDURE - Step 3

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE RELAY (C/OPN) 

    Result: 

    OK 

    See step  13

  13. CHECK HARNESS AND CONNECTOR (C/OPN RELAY - FUEL PUMP CONTROL ECU) 
    1. Remove the C/OPN relay from the No. 3 engine room relay block assembly.
    2. Disconnect the fuel pump control ECU connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      3 (C/OPN relay) - U27-4 (+B) Always Below 1 Ω
      3 (C/OPN relay) or U27-4 (+B) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  14

  14. CHECK HARNESS AND CONNECTOR (EFI MAIN NO. 2 RELAY - C/OPN RELAY) 
    1. Remove the EFI MAIN NO. 2 relay from the No. 3 engine room relay block assembly.
    2. Remove the C/OPN relay from the No. 3 engine room relay block assembly.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      3 (EFI MAIN NO. 2 relay) - 5 (C/OPN relay) Always Below 1 Ω
      3 (EFI MAIN NO. 2 relay) - 1 (C/OPN relay) Always Below 1 Ω
      3 (EFI MAIN NO. 2 relay) or 5 (C/OPN relay) - Body ground Always 10 kΩ or higher
      3 (EFI MAIN NO. 2 relay) or 1 (C/OPN relay) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  15

  15. INSPECT RELAY (EFI MAIN NO. 2) 
    1. Inspect the EFI MAIN NO. 2 relay.

      Refer to PROCEDURE - Step 4

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE RELAY (EFI MAIN NO. 2) 

    Result: 

    OK 

    See step  16

  16. CHECK HARNESS AND CONNECTOR (EFI MAIN NO. 2 RELAY - ECM) 
    1. Remove the EFI MAIN NO. 2 relay from the No. 3 engine room relay block assembly.
    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
      1 (EFI MAIN NO. 2 relay) - A77-3 (MREL) Always Below 1 Ω
      1 (EFI MAIN NO. 2 relay) or A77-3 (MREL) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  17

  17. CHECK HARNESS AND CONNECTOR (EFI MAIN NO. 2 RELAY - BODY GROUND) 
    1. Remove the EFI MAIN NO. 2 relay from the No. 3 engine room relay block assembly.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      2 (EFI MAIN NO. 2 relay) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - EFI MAIN NO. 2 RELAY) 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  18. INSPECT FUEL PUMP CONTROL ECU 
    GTY1171558Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *1 Fuel Pump Control ECU - -
    1. Remove the fuel pump control ECU.

      Refer to REMOVAL [09/2014 - ]

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      U62-1 (+B) - U62-3 (GND) Always 200 Ω or higher
      U62-1 (+B) - U62-2 (FPC) Always 2 kΩ or higher
      U62-2 (FPC) - U62-3 (GND) Always 10 kΩ or higher
      U61-1 (FPG) - U62-3 (GND) Always 1 kΩ or higher
      U61-2 (FPU) - U62-3 (GND) Always 2 kΩ or higher
      U61-3 (FPV) - U62-3 (GND) Always 2 kΩ or higher
      U61-4 (FPW) - U62-3 (GND) Always 2 kΩ or higher

      HINT: 

      This procedure checks for an internal short of the fuel pump control ECU when its transistor is stuck on.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE FUEL PUMP CONTROL ECU. Refer to  REMOVAL [09/2014 - ] 

    Result: 

    OK 

    See step  19

  19. CHECK HARNESS AND CONNECTOR (POWER SOURCE OF FUEL PUMP CONTROL ECU) 
    GTY1172209Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Front view of wire harness connector
    (to Fuel Pump Control ECU)
    1. Disconnect the fuel pump control ECU connector.
    2. Turn the engine switch on (IG).
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      U62-1 (+B) - U62-3 (GND) Engine switch on (IG) 11 to 14 V

      HINT: 

      Make a note of the measured voltage as it may be used in a following Active Test.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  24

    Result: 

    OK 

    See step  20

  20. CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU - ECM) 
    1. Disconnect the fuel pump control 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
      U62-2 (FPC) - A78-1 (FPC) Always Below 1 Ω
      U62-2 (FPC) or A78-1 (FPC) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  21

  21. PERFORM ACTIVE TEST USING TECHSTREAM (FUEL PUMP SINGLE PHASE ENERGIZATION) 
    GTY1173125Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *1 Fuel Pump Control ECU - -
    1. Disconnect the U61 fuel pump control ECU connector.
    2. Connect the Techstream to the DLC3.
    3. Turn the engine switch on (IG).
    4. Turn the Techstream on.
    5. Enter the following menus: Powertrain / Engine / Active Test / Fuel Pump Single Phase Energization.

      Powertrain > Engine > Active Test 

      Tester Display
      Fuel Pump Single Phase Energization
    6. Operate the fuel pump control ECU 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
      U61-2 (FPU) - Body ground U Phase 4.4 to 8.4 V*
      U61-3 (FPV) - Body ground V Phase 4.4 to 8.4 V*
      U61-4 (FPW) - Body ground W Phase 4.4 to 8.4 V*

      HINT: 

      • *: This Active Test restricts the fuel pump control ECU output duty cycle to 50%. Therefore, the output voltage of the fuel pump control ECU will be approximately 50% of the power source voltage measured in a previous step.
      • Before performing this inspection, check that the battery voltage is between 11 and 14 V (not depleted).

      Result

      Result Proceed to
      The U phase, V phase and W phase are all normal A
      The U phase, V phase or W phase is abnormal B
      The U phase, V phase and W phase are all abnormal C

    Result: 

    B 

    REPLACE FUEL PUMP CONTROL ECU. Refer to  REMOVAL [09/2014 - ] 

    Result: 

    C 

    See step  23

    Result: 

    A 

    See step  22

  22. CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU - FUEL PUMP (FOR LOW PRESSURE SIDE)) 
    1. Disconnect the fuel pump control ECU connector.
    2. Disconnect the fuel pump (for low pressure side) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      U61-2 (FPU) - U60-3 (BLPU) Always Below 1 Ω
      U61-3 (FPV) - U60-4 (BLPV) Always Below 1 Ω
      U61-4 (FPW) - U60-2 (BLPW) Always Below 1 Ω
      U61-2 (FPU) or U60-3 (BLPU) - Body ground and other terminals Always 10 kΩ or higher
      U61-3 (FPV) or U60-4 (BLPV) - Body ground and other terminals Always 10 kΩ or higher
      U61-4 (FPW) or U60-2 (BLPW) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

      HINT: 

      Perform "Inspection After Repair" after replacing the fuel pump (for low pressure side).

      Refer to INITIALIZATION [09/2014 - ]

    Result: 

    OK 

    REPLACE FUEL PUMP (FOR LOW PRESSURE SIDE). Refer to  REMOVAL [09/2014 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  23. INSPECT ECM (FPC TERMINAL) 
    GTY1170290Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Front view of wire harness connector
    (to Fuel Pump Control ECU)
    1. Disconnect the fuel pump control ECU connector.
    2. Connect the Techstream to the DLC3.
    3. Turn the engine switch on (IG).
    4. Turn the Techstream on.
    5. Enter the following menus: Powertrain / Engine / Active Test / Fuel Pump Single Phase Energization.

      Powertrain > Engine > Active Test 

      Tester Display
      Fuel Pump Single Phase Energization
    6. Operate the fuel pump control ECU using the Active Test function and measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Techstream Operation Specified Condition
      U60-2 (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.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE FUEL PUMP CONTROL ECU. Refer to  REMOVAL [09/2014 - ] 

    Result: 

    NG 

    REPLACE ECM. Refer to  REMOVAL [09/2014 - ] 

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      U62-3 (GND) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  25

  25. INSPECT EFI MAIN NO. 2 RELAY 
    1. Inspect the EFI MAIN NO. 2 relay.

      Refer to PROCEDURE - Step 4

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE EFI MAIN NO. 2 RELAY 

    Result: 

    OK 

    See step  26

  26. CHECK HARNESS AND CONNECTOR (POWER SOURCE VOLTAGE OF EFI MAIN NO. 2 RELAY) 
    1. Remove the EFI MAIN NO. 2 relay from the No. 3 engine room relay block assembly.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      5 (EFI MAIN NO. 2 relay) - Body ground Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - EFI-MAIN NO. 2 RELAY) 

    Result: 

    OK 

    See step  27

  27. CHECK HARNESS AND CONNECTOR (ECM - EFI-MAIN NO. 2 RELAY) 
    1. Disconnect the ECM connector.
    2. Remove the EFI MAIN NO. 2 relay from the No. 3 engine room relay block assembly.
    3. Disconnect the 2G semiconductor power integration ECU connector.

      HINT: 

      Remove the EFI-MAIN relay connected between the checked terminals as the coil inside the relay influences the measurement value.

    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A77-3 (MREL) - 1 (EFI MAIN NO. 2 relay) Always Below 1 Ω
      A77-3 (MREL) or 1 (EFI MAIN NO. 2 relay) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  28

  28. CHECK HARNESS AND CONNECTOR (EFI MAIN NO. 2 RELAY - BODY GROUND) 
    1. Remove the EFI MAIN NO. 2 relay from the No. 3 engine room relay block assembly.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      2 (EFI MAIN NO. 2 relay) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  29

  29. CHECK HARNESS AND CONNECTOR (EFI MAIN NO. 2 RELAY - FUEL PUMP CONTROL ECU) 
    1. Remove the EFI MAIN NO. 2 relay from the No. 3 engine room relay block assembly.
    2. Disconnect the fuel pump control ECU connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      3 (EFI MAIN NO. 2 relay) - U62-1 (+B) Always Below 1 Ω
      3 (EFI MAIN NO. 2 relay) or U62-1 (+B) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    GO TO ECM POWER SOURCE CIRCUIT. Refer to  ECM Power Source Circuit [09/2014 - ]  

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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