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Fuel Pump Control Circuit: Procedure

  1. PERFORM ACTIVE TEST USING TECHSTREAM (FUEL PUMP) 
    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 and ECT / Active Test / Control the Fuel Pump / Speed.
    4. Check whether operating sounds can be heard while operating the fuel pump using the Techstream.

      OK

      Operating sounds can be heard from fuel pump.

    NG → See step   5 

    OK: Go to next step 

  2. CHECK HARNESS AND CONNECTOR (FUEL PUMP ECU - ECM, BODY GROUND) 
    Fig 1: Identifying N2 Fuel Pump ECU And A38 ECM Connector Terminals
    GTY148672Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the N2 fuel pump ECU connector.
    2. Disconnect the A38 ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      N2-5 (FPC) - A38-52 (FPC) Always Below 1 Ω
      N2-4 (DI) - A38-18 (DI) Always Below 1 Ω
      N2-6 (E) - Body ground Always Below 1 Ω
      N2-5 (FPC) or A38-52 (FPC) - Body ground Always 10 kΩ or higher
      N2-4 (DI) or A38-18 (DI) - Body ground Always 10 kΩ or higher
      N2-1 (FP-) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  3. REPLACE FUEL PUMP ECU 
    1. Replace the fuel pump ECU. Refer to REMOVAL .

    NEXT: Go to next step 

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

      OK

      Malfunction has been repaired successfully.

    NG → See step   18 

    OK → END 

  5. INSPECT CIRCUIT OPENING RELAY (C/OPN) 
    Fig 2: Identifying Circuit Opening Relay (C/OPN)
    GTY102844Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the circuit opening relay (C/OPN) from the engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      3 - 5 Battery voltage not applied 10 kΩ or higher
      Battery voltage applied to terminals 1 and 2 Below 1 Ω

    NG → REPLACE CIRCUIT OPENING RELAY (C/OPN) 

    OK: Go to next step 

  6. INSPECT CIRCUIT OPENING RELAY (POWER SOURCE VOLTAGE) 
    Fig 3: Identifying Engine Room Relay Block
    GTY147810Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the circuit opening relay (C/OPN) from the engine room relay block.
    2. Turn the engine switch on (IG).
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      C/OPN relay (2) - Body ground Engine switch on (IG) 11 to 14 V
      C/OPN relay (5) - Body ground Engine switch on (IG) 11 to 14 V

    NG → See step   13 

    OK: Go to next step 

  7. CHECK HARNESS AND CONNECTOR (CIRCUIT OPENING RELAY - ECU, FUEL PUMP ECU) 
    Fig 4: Identifying A38 ECM And N2 Fuel Pump ECU Connector Terminals
    GTY131020Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the circuit opening relay (C/OPN) from the engine room relay block.
    2. Disconnect the A38 ECM connector.
    3. Disconnect the N2 fuel pump ECU connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      C/OPN relay (1) - A38-48 (FC) Always Below 1 Ω
      C/OPN relay (3) - N2-3 (+B) Always Below 1 Ω
      C/OPN relay (1) or A38-48 (FC) - Body ground Always 10 kΩ or higher
      C/OPN relay (3) or N2-3 (+B) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  8. CHECK HARNESS AND CONNECTOR (FUEL PUMP - FUEL PUMP ECU) 
    Fig 5: Identifying N1 Fuel Pump And N2 Fuel Pump ECU Connector Terminals
    GTY148676Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the N1 fuel pump connector.
    2. Disconnect the N2 fuel pump ECU connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      N1-4 (B2) - N2-2 (FP) Always Below 1 Ω
      N1-5 (E2) - N2-1 (FP-) Always Below 1 Ω
      N1-4 (B2) or N2-2 (FP) - Body ground Always 10 kΩ or higher
      N1-5 (E2) or N2-1 (FP-) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  9. INSPECT FUEL PUMP 
    1. Inspect the fuel pump. Refer to INSPECTION .

    NG → See step   17 

    OK: Go to next step 

  10. CHECK HARNESS AND CONNECTOR (FUEL PUMP ECU - ECM, BODY GROUND) 
    Fig 6: Identifying N2 Fuel Pump ECU And A38 ECM Connector Terminals
    GTY148673Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the N2 fuel pump ECU connector.
    2. Disconnect the A38 ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      N2-5 (FPC) - A38-52 (FPC) Always Below 1 Ω
      N2-4 (DI) - A38-18 (DI) Always Below 1 Ω
      N2-6 (E) - Body ground Always Below 1 Ω
      N2-5 (FPC) or A38-52 (FPC) - Body ground Always 10 kΩ or higher
      N2-4 (DI) or A38-18 (DI) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  11. REPLACE FUEL PUMP ECU 
    1. Replace the fuel pump ECU. Refer to REMOVAL .

    NEXT: Go to next step 

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

      OK

      Malfunction has been repaired successfully.

    NG → See step   18 

    OK → END 

  13. CHECK HARNESS AND CONNECTOR (CIRCUIT OPENING RELAY - EFI NO. 2 RELAY, IGN FUSE) 
    Fig 7: Identifying IGN Fuse, Circuit Opening Relay (C/OPN) And Relay (EFI NO. 2)
    GTY148691Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the circuit opening relay (C/OPN) from the engine room relay block.
    2. Remove the EFI NO. 2 relay (EFI NO. 2) from the engine room relay block.
    3. Remove the IGN fuse from the engine room relay block.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

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

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  14. INSPECT EFI NO. 2 RELAY (EFI NO. 2) 
    Fig 8: Identifying EFI NO. 2 Relay
    GTY102844Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the EFI NO. 2 relay (EFI NO. 2) from the engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      3 - 5 Battery voltage not applied 10 kΩ or higher
      Battery voltage applied to terminals 1 and 2 Below 1 Ω

    NG → REPLACE EFI NO. 2 RELAY (EFI NO. 2) 

    OK: Go to next step 

  15. CHECK HARNESS AND CONNECTOR (EFI NO. 2 RELAY - INTEGRATION RELAY, BATTERY AND BODY GROUND) 
    Fig 9: Identifying EFI Main 2 Fuse And 1B Integration Relay Connector
    GTY135483Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the EFI MAIN 2 fuse from the engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      EFI MAIN 2 fuse Always Below 1 Ω
    3. Reinstall the EFI MAIN 2 fuse.
    4. Remove the EFI NO. 2 relay (EFI NO. 2) from the engine room relay block.
    5. Remove the integration relay from the engine room relay block.
    6. Disconnect the 1B integration relay connector.
    7. Disconnect the cable from the positive (+) battery terminal.
    8. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      EFI NO. 2 relay (1) - 1B-4 Always Below 1 Ω
      EFI NO. 2 relay (5) - Positive (+) battery cable Always Below 1 Ω
      EFI NO. 2 relay (2) - Body ground Always Below 1 Ω
      EFI NO. 2 relay (1) or 1B-4 - Body ground Always 10 kΩ or higher
      EFI NO. 2 relay (5) or Positive (+) battery cable - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   16 

  16. GO TO ECM POWER SOURCE CIRCUIT. Refer to  ECM Power Source Circuit  
  17. REPLACE FUEL PUMP. Refer to  REMOVAL 
  18. REPLACE ECM. Refer to  REMOVAL 
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