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Inspection Procedure

  1. CHECK FUEL PUMP OPERATION 
    1. Check the fuel pressure (see ON-VEHICLE INSPECTION ).

      HINT:

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

    OK: Go to step   10 

    NG: GO TO NEXT STEP 

  2. PERFORM ACTIVE TEST BY INTELLIGENT TESTER OR TECHSTREAM (OPERATE CIRCUIT OPENING RELAY (C/OPN)) 
    1. Connect the Intelligent tester or Techstream to the DLC3.
    2. Turn the engine switch on (IG) and turn the tester ON.
    3. Enter the following menus:
      1. Intelligent tester - Select: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / FUEL PUMP / SPD.
      2. Techstream - Select: Powertrain / Engine / Active Test / Activate the Fuel Pump Speed Control.
    4. Check whether operating sounds can be heard while operating the relay using the tester.

      OK: Operating sounds can be heard from relay. 

    OK: Go to step   5 

    NG: GO TO NEXT STEP 

  3. INSPECT CIRCUIT OPENING RELAY (C/OPN) 
    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 

      CIRCUIT OPENING RELAY (C/OPN)

      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
      Fig 1: Identifying C/OPN Relay Terminal
      G04942983Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE CIRCUIT OPENING RELAY (C/ OPN) (See  CIRCUIT OPENING RELAY   ) 

    OK: GO TO NEXT STEP 

  4. INSPECT ECM (FC VOLTAGE) 
    1. Turn the engine switch on (IG).
    2. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      ECM (FC VOLTAGE)

      Tester Connection Switch Condition Specified Condition
      A14-5 (FC) - E3-1 (E1) Engine switch on (IG) 11 to 14 V
      Fig 2: Identifying ECM Connector Pin Terminal
      G04942984Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: REPLACE ECM (See  REMOVAL   ) 

    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 (see ECM POWER SOURCE CIRCUIT  ).

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: GO TO NEXT STEP 

  6. INSPECT FUEL PUMP RELAY (F/PMP) (See  INSPECTION PROCEDURE  ) 

    NG: REPLACE FUEL PUMP RELAY (F/PMP) (See  FUEL PUMP RELAY   ) 

    OK: GO TO NEXT STEP 

  7. INSPECT FUEL PUMP ASSEMBLY 
    1. Inspect the fuel pump resistance.
      1. Measure the resistance according to the value(s) in the table below.

        Standard resistance 

        FUEL PUMP ASSEMBLY

        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.
      Fig 3: Identifying Fuel Pump Assembly Connector Terminal
      G04942985Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE FUEL PUMP ASSEMBLY  (See REMOVAL )

    OK: GO TO NEXT STEP 

  8. CHECK HARNESS AND CONNECTOR (FUEL PUMP - FUEL PUMP RELAY (F/PMP), BODY GROUND) 
    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) 

        FUEL PUMP - FUEL PUMP RELAY (F/PMP), BODY GROUND (CHECK FOR OPEN)

        Tester Connection Condition Specified Condition
        S11-4-F/PMP relay (3) Always Below 1 Ω

        Standard resistance (Check for short) 

        FUEL PUMP - FUEL PUMP RELAY (F/PMP), BODY GROUND (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) 

        S11 FUEL PUMP - BODY GROUND (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 

    Fig 4: Identifying S11 Fuel Pump Connector
    G04942986Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: GO TO NEXT STEP 

  9. CHECK HARNESS AND CONNECTOR (CIRCUIT OPENING RELAY (C/OPN) - FUEL PUMP RELAY (F/PMP)) 
    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) 

      CIRCUIT OPENING RELAY (C/OPN) - FUEL PUMP RELAY (F/PMP) (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) 

      CIRCUIT OPENING RELAY (C/OPN) - FUEL PUMP RELAY (F/PMP) (CHECK FOR SHORT)

      Tester Connection Condition Specified Condition
      C/OPN relay (3) or F/ PMP relay (4) - Body ground Always 10 kΩ or higher
      Fig 5: Identifying C/OPN Relay And F/PMP Relay Terminal
      G04942987Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    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) (See  INSPECTION PROCEDURE  ) 

    NG: REPLACE FUEL PUMP RELAY (F/PMP) (See  FUEL PUMP RELAY   ) 

    OK: GO TO NEXT STEP 

  11. INSPECT FUEL PUMP RESISTOR (RESISTANCE) 
    1. Inspect the fuel pump resistor resistance.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      FUEL PUMP RESISTOR (RESISTANCE)

      Tester Connection Condition Specified Condition
      1-2 20°C (68°F) 0.941 to 0.999 Ω
      Fig 6: Checking Fuel Pump Resistor Resistance
      G04942988Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE FUEL PUMP RESISTOR  (See REMOVAL )

    OK: GO TO NEXT STEP 

  12. CHECK HARNESS AND CONNECTOR (FUEL PUMP RESISTOR - FUEL PUMP RELAY (F/ PMP), FUEL PUMP) 
    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) 

        FUEL PUMP RESISTOR - FUEL PUMP RELAY (F/ PMP), FUEL PUMP (CHECK FOR OPEN)

        Tester Connection Condition Specified Condition
        F/PMP relay (4) -A16-1 Always Below 1 Ω

        Standard resistance (Check for short) 

        FUEL PUMP RESISTOR - FUEL PUMP RELAY (F/ PMP), FUEL PUMP (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) 

        A16 FUEL PUMP RESISTOR - S11 FUEL PUMP (CHECK FOR OPEN)

        Tester Connection Condition Specified Condition
        A16-2 - S11-4 Always Below 1 Ω

        Standard resistance (Check for short) 

        A16 FUEL PUMP RESISTOR OR S11 FUEL PUMP - BODY GROUND (CHECK FOR SHORT)

        Tester Connection Condition Specified Condition
        A16-2 or S11-4-Body ground Always 10 kΩ or higher
        Fig 7: Identifying A16 Fuel Pump Resistor Connector And F/Pmp Relay Terminal
        G04942989Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      4. Reconnect the fuel pump resistor connector.
      5. Reconnect the fuel pump connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE (See  PROBLEM SYMPTOMS TABLE  )