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Fuel Pump Control Circuit: Procedure

  1. CHECK FUEL PUMP OPERATION 
    1. Check the fuel pressure. Refer to ON-VEHICLE INSPECTION - Step 2 .

      HINT: 

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

    OK → See step   10 

    NG: Go to next step 

  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 / 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.

    OK → See step   5 

    NG: Go to next step 

  3. INSPECT CIRCUIT OPENING RELAY (C/OPN) 
    Fig 1: Identifying Relay Terminals
    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

    NG → See step   13 

    OK: Go to next step 

  4. INSPECT ECM (FC VOLTAGE) 
    Fig 2: Identifying E3 And A14 ECM Connectors
    GTY288008Courtesy 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

    OK → See step   14 

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

  5. INSPECT ECM POWER SOURCE CIRCUIT 
    1. Inspect the ECM power source circuit. Refer to ECM Power Source Circuit .

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  6. INSPECT FUEL PUMP RELAY (F/PMP). Refer to  PROCEDURE - Step 2 

    NG → See step   15 

    OK: Go to next step 

  7. INSPECT FUEL PUMP ASSEMBLY 
    Fig 3: Identifying Fuel Pump Assembly Connector Terminal
    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.

    NG → See step   16 

    OK: Go to next step 

  8. CHECK HARNESS AND CONNECTOR (FUEL PUMP - FUEL PUMP RELAY (F/PMP), BODY GROUND) 
    Fig 4: Checking Harness And Connector (Fuel Pump - Fuel Pump Relay (F/PMP), Body Ground)
    GTY272711Courtesy 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.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  9. CHECK HARNESS AND CONNECTOR (CIRCUIT OPENING RELAY (C/OPN) - FUEL PUMP RELAY (F/PMP)) 
    Fig 5: Identifying C/OPN Relay And F/PMP Relay
    GTY288280Courtesy 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

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

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

  10. INSPECT FUEL PUMP RELAY (F/PMP). Refer to  PROCEDURE - Step 2 

    NG → See step   19 

    OK: Go to next step 

  11. INSPECT FUEL PUMP RESISTOR (RESISTANCE) 
    Fig 6: Inspecting Fuel Pump Resistor
    GTY288143Courtesy 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   17 

    OK: Go to next step 

  12. CHECK HARNESS AND CONNECTOR (FUEL PUMP RESISTOR - FUEL PUMP RELAY (F/PMP), FUEL PUMP) 
    Fig 7: Identifying A16 Fuel Pump Resistor And S11 Fuel Pump Connector With Fuel Pump Relay
    GTY285692Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Check the harness and connector between the fuel pump relay and fuel pump resistor.
      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.
    2. Check the harness and connector between the fuel pump resistor and fuel pump.
      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.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   18 

  13. REPLACE CIRCUIT OPENING RELAY (C/OPN). Refer to  ON-VEHICLE INSPECTION - Step 3 
  14. REPLACE ECM. Refer to  REMOVAL 
  15. REPLACE FUEL PUMP RELAY (F/PMP). Refer to  ON-VEHICLE INSPECTION - Step 3 
  16. REPLACE FUEL PUMP ASSEMBLY. Refer to  REMOVAL 
  17. REPLACE FUEL PUMP RESISTOR. Refer to  REMOVAL 
  18. PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE 
  19. REPLACE FUEL PUMP RELAY (F/PMP). Refer to  ON-VEHICLE INSPECTION - Step 3 
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