LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 2013 >> LS 600hL >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Diagnostic Codes (P1276-U0293) & Circuit Tests) >> SFI System >> Circuit Tests >> Fuel Pump Control Circuit >> Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Fuel Pump Control Circuit: Procedure

  1. CHECK FUEL PUMP OPERATION 
    1. Check the fuel pressure. Refer to ON-VEHICLE INSPECTION [09/2012 - ] - Step 2 .

      HINT: 

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

    NG → See step   5 

    OK: Go to next step 

  2. INSPECT FUEL PUMP RELAY (F/PMP) 
    1. Inspect the F/PMP relay. Refer to ON-VEHICLE INSPECTION [09/2012 - ] .

    NG → See step   18 

    OK: Go to next step 

  3. INSPECT FUEL PUMP RESISTOR 
    GTY122493Courtesy 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

    NG → See step   19 

    OK: Go to next step 

  4. CHECK HARNESS AND CONNECTOR (CIRCUIT OPENING RELAY (C/OPN) TO FUEL PUMP) 
    GTY355114Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Check the harness and connector.
      1. Remove the C/OPN relay and 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

        Tester Connection Condition Specified Condition
        C/OPN relay (3) - F/PMP relay (4) Always Below 1 Ω
        C/OPN relay (3) - A16-1 Always Below 1 Ω
        C/OPN relay (3) or F/PMP relay (4) - Body ground Always 10 kΩ or higher
        C/OPN relay (3) or A16-1 - Body ground Always 10 kΩ or higher
    2. Check the harness and connector.
      1. Remove the F/PMP relay from the engine room No. 2 relay block.
      2. Disconnect the A16 fuel pump resistor connector.
      3. Disconnect the S11 fuel pump connector.
      4. Measure the resistance according to the value(s) in the table below.

        Standard resistance

        Tester Connection Condition Specified Condition
        F/PMP relay (3) - S11-4 Always Below 1 Ω
        A16-2 - S11-4 Always Below 1 Ω
        F/PMP relay (3) or S11-4 - Body ground Always 10 kΩ or higher
        A16-2 or S11-4 - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   24 

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

      OK

      Operating sounds can be heard from relay.

    NG → See step   14 

    OK: Go to next step 

  6. INSPECT FUSE (EFI MAIN) 
    GTY148448Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the EFI MAIN fuse 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
      EFI MAIN fuse Always Below 1 Ω

    NG → CHECK FOR SHORT IN ALL HARNESSES AND CONNECTORS CONNECTED TO FUSE AND REPLACE FUSE 

    OK: Go to next step 

  7. INSPECT EFI RELAY (EFI MAIN) 
    1. Inspect the EFI MAIN relay. Refer to ON-VEHICLE INSPECTION [09/2012 - ] .

    NG → See step   20 

    OK: Go to next step 

  8. CHECK HARNESS AND CONNECTOR (CIRCUIT OPENING RELAY (C/OPN) - EFI MAIN RELAY) 
    GTY148449Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the EFI MAIN relay and 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
      EFI MAIN relay (3) - C/OPN relay (5) Always Below 1 Ω
      EFI MAIN relay (3) or C/OPN relay (5) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  9. INSPECT FUEL PUMP RELAY (F/PMP) 
    1. Inspect the F/PMP relay. Refer to ON-VEHICLE INSPECTION [09/2012 - ] .

    NG → See step   18 

    OK: Go to next step 

  10. INSPECT FUEL PUMP RESISTOR 
    1. Inspect the fuel pump resistor. Refer to INSPECTION [09/2012 - ] .

    NG → See step   19 

    OK: Go to next step 

  11. CHECK HARNESS AND CONNECTOR (CIRCUIT OPENING RELAY (C/OPN) TO FUEL PUMP) 
    GTY355114Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Check the harness and connector.
      1. Remove the C/OPN relay and 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

        Tester Connection Condition Specified Condition
        C/OPN relay (3) - F/PMP relay (4) Always Below 1 Ω
        C/OPN relay (3) - A16-1 Always Below 1 Ω
        C/OPN relay (3) or F/PMP relay (4) - Body ground Always 10 kΩ or higher
        C/OPN relay (3) or A16-1 - Body ground Always 10 kΩ or higher
    2. Check the harness and connector.
      1. Remove the F/PMP relay from the engine room No. 2 relay block.
      2. Disconnect the A16 fuel pump resistor connector.
      3. Disconnect the S11 fuel pump connector.
      4. Measure the resistance according to the value(s) in the table below.

        Standard resistance

        Tester Connection Condition Specified Condition
        F/PMP relay (3) - S11-4 Always Below 1 Ω
        A16-2 - S11-4 Always Below 1 Ω
        F/PMP relay (3) or S11-4 - Body ground Always 10 kΩ or higher
        A16-2 or S11-4 - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  12. INSPECT FUEL PUMP 
    1. Inspect the fuel pump. Refer to INSPECTION [09/2012 - ] - Step 1 .

    NG → See step   21 

    OK: Go to next step 

  13. CHECK HARNESS AND CONNECTOR (FUEL PUMP - BODY GROUND) 
    GTY148450Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the S11 fuel pump connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection Condition Specified Condition
      S11-5 - Body ground Always Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → REPAIR OR REPLACE HARNESS OR CONNECTOR (EFI MAIN RELAY - BATTERY) 

  14. INSPECT CIRCUIT OPENING RELAY (C/OPN) 
    1. Inspect the C/OPN relay. Refer to ON-VEHICLE INSPECTION [09/2012 - ] .

    NG → See step   22 

    OK: Go to next step 

  15. CHECK HARNESS AND CONNECTOR (CIRCUIT OPENING RELAY (C/OPN) - EFI-B FUSE) 
    GTY143588Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the C/OPN relay and EFI-B fuse 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
      C/OPN relay (1) - EFI-B fuse (2) Always Below 1 Ω
      C/OPN relay (1) or EFI-B fuse (2) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  16. CHECK CIRCUIT OPENING RELAY [C/OPN] (POWER SOURCE) 
    GTY148451Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the C/OPN relay from the engine room No. 2 relay block.
    2. Measure the voltage according to the value(s) in the table below.

      Standard voltage

      Tester Connection Condition Specified Condition
      C/OPN relay (1) - Body ground Power switch on (IG) 11 to 14 V

    NG → See step   23 

    OK: Go to next step 

  17. CHECK HARNESS AND CONNECTOR (CIRCUIT OPENING RELAY (C/OPN) - ECM) 
    GTY148452Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the C/OPN relay from the engine room No. 2 relay block.
    2. Disconnect the A14 ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection Condition Specified Condition
      C/OPN relay (2) - A14-5 (FC) Always Below 1 Ω
      C/OPN relay (2) or A14-5 (FC) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   25 

  18. REPLACE FUEL PUMP RELAY (F/PMP). Refer to  ON-VEHICLE INSPECTION [09/2012 - ] 
  19. REPLACE FUEL PUMP RESISTOR. Refer to  REMOVAL [09/2012 - ] 
  20. REPLACE EFI MAIN RELAY. Refer to  ON-VEHICLE INSPECTION [09/2012 - ] 
  21. REPLACE FUEL PUMP. Refer to  REMOVAL [09/2012 - ] 
  22. REPLACE CIRCUIT OPENING RELAY. Refer to  ON-VEHICLE INSPECTION [09/2012 - ] 
  23. GO TO ECM POWER SOURCE CIRCUIT. Refer to  ECM Power Source Circuit  
  24. REPLACE ECM. Refer to  REMOVAL [09/2012 - ] 
  25. REPLACE ECM. Refer to  REMOVAL [09/2012 - ] 
scientia non olet · About LEMON Manuals