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Home >> Lexus >> 2007 >> IS 250 AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (4GR-FSE) - System And Circuit Testing, On-Vehicle Inspection, Removal, Inspection & Installation >> Fuel Pump Control Circuit >> Inspection Procedure
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Inspection Procedure

  1. CHECK FUEL PUMP (FUEL PUMP OPERATION) 
    1. Check if there is pressure in the fuel inlet hose.

      HINT:

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

    OK: Go to step  12

    NG: Go to next step 

  2. PERFORM ACTIVE TEST BY INTELLIGENT TESTER (OPERATE CIRCUIT OPENING RELAY) 
    1. Connect the intelligent tester to the DLC3.
    2. Turn the engine switch on (IG) and turn the intelligent tester on.
    3. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / FUEL PUMP / SPD.
    4. Check the operation of the relay while operating it using the intelligent tester.

      OK: 

      Operating noise can be heard from the relay. 

    OK: Go to step  8

    NG: Go to next step 

  3. INSPECT ECM POWER SOURCE CIRCUIT 

    NG: REPAIR OR REPLACE POWER SOURCE CIRCUIT 

    OK: Go to next step 

  4. INSPECT FUSE (F/PMP FUSE) 
    1. Remove the F/PMP fuse from the engine room J/B and R/B No. 2.
    2. Measure the resistance of the F/PMP fuse.
      Fig 1: Identifying F/PMP Fuse
      G05316603Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard resistance: 

      Below 1 Ω 

    NG: REPLACE FUSE 

    OK: Go to next step 

  5. INSPECT INTEGRATION RELAY (EFI NO. 2 RELAY) 
    1. Remove the integration relay from the engine room J/B and R/B No. 2.
    2. Measure the resistance according to the value (s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      2B-4 - 2C-1 10 kΩ or higher
      2B-4 - 2C-1 Below 1 Ω (when battery voltage applied to terminals 2B-3 and 2B-2)
      Fig 2: Identifying Integration Relay Connector Terminals
      G05316604Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE INTEGRATION RELAY 

    OK: Go to next step 

  6. INSPECT INTEGRATION RELAY (C/OPN RELAY) 
    1. Remove the integration relay from the engine room J/B and R/B No. 2.
    2. Measure the resistance according to the value (s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      2B-6 - 2B-8 10 kΩ or higher
      2B-6 - 2B-8 Below 1 Ω (when battery voltage applied to terminals 2B-6 and 2B-7)
      Fig 3: Identifying Integration Relay Connector Terminals
      G05316605Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE INTEGRATION RELAY 

    OK: Go to next step 

  7. 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 

      VOLTAGE SPECIFICATION

      Tester Connection Specified Condition
      FC (A5-14) - E1 (E4-7) 9 to 14 V
      Fig 4: Identifying ECM Connector Terminals
      G05316606Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: REPLACE ECM 

    NG: CHECK AND REPAIR HARNESS AND CONNECTOR (ECM - CIRCUIT OPENING RELAY) 

  8. INSPECT F/PMP RELAY 
    1. Remove the F/PMP relay from the engine room J/B and R/B No. 2.
    2. Measure the resistance according to the value (s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      3 - 4 10 kΩ or higher
      3 - 4 Below 1 Ω (when battery voltage applied to terminals 1 and 2)
      Fig 5: Identifying F/PMP Relay Connector Terminals
      G05316607Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE F/PMP RELAY 

    OK: Go to next step 

  9. INSPECT FUEL PUMP 
    1. Inspect fuel pump resistance.
      1. Measure the resistance between terminals 4 and 5.

        Standard resistance: 

        0.2 to 3.0 Ω at 20°C (68°F) 

    2. Inspect 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 switch at the battery side.

    NG: REPLACE FUEL PUMP 

    Fig 6: Identifying Fuel Pump Connector Terminals
    G05316608Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  10. CHECK HARNESS AND CONNECTOR (FUEL PUMP - F/PMP RELAY) 
    1. Check the harness and the connectors between the fuel pump and the F/PMP relay.
      1. Disconnect the fuel pump connector.
      2. Remove the F/PMP relay from the engine room J/B and R/B No. 2.
      3. Measure the resistance according to the value (s) in the table below.

        Standard resistance (Check for open) 

        RESISTANCE SPECIFICATION

        Tester Connection Specified Condition
        Fuel pump (Q14-4) - F/PMP relay (4) Below 1 Ω

        Standard resistance (Check for short) 

        RESISTANCE SPECIFICATION

        Tester Connection Specified Condition
        Fuel pump (Q14-4) or F/PMP (4) - Body ground 10 kΩ or higher
    2. Check the harness and the connectors between the fuel pump and body ground.
      1. Disconnect the fuel pump connector.
      2. Measure the resistance according to the value (s) in the table below.

        Standard resistance (Check for open) 

        RESISTANCE SPECIFICATION

        Tester Connection Specified Condition
        Fuel pump (Q14-5) - Body ground 10 kΩ or higher
        Fig 7: Identifying Fuel Pump And F/PMP Relay Connector Terminals
        G05316609Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  11. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY - F/PMP RELAY) 
    1. Remove the integration relay from the engine room J/B and R/B No. 2.
    2. Remove the F/PMP relay from the engine room J/B and R/B No. 2.
    3. Measure the resistance according to the value (s) in the table below.

      Standard resistance (Check for open) 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      Integration relay (2B-8) - F/PMP relay (1) Below 1 Ω
      Integration relay (2B-8) - F/PMP relay (3) Below 1 Ω

      Standard resistance (Check for short) 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      Circuit opening relay (2B-8) or F/PMP relay (1) - Body ground 10 kΩ or higher
      Circuit opening relay (2B-8) or F/PMP relay (3) - Body ground 10 kΩ or higher
      Fig 8: Identifying Integration Relay And F/PMP Relay Connector Terminals
      G05316610Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPAIR OR REPLACE INTEGRATION RELAY 

  12. INSPECT F/PMP RELAY 
    1. Remove the F/PMP relay from the engine room J/B and R/B No. 2.
    2. Measure the resistance according to the value (s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      3 - 4 10 kΩ or higher
      3 - 4 Below 1 Ω (when battery voltage applied to terminals 1 and 2)
      Fig 9: Identifying F/PMP Relay Connector Terminals
      G05316611Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE F/PMP RELAY 

    OK: Go to next step 

  13. INSPECT FUEL PUMP RESISTER 
    1. Measure the resistance of the fuel pump resistor.

      Standard resistance: 

      0.30 to 0.34 Ω at 20°C (68°F) 

    NG: REPLACE FUEL PUMP RESISTER 

    Fig 10: Identifying Resistance Between Fuel Pump Resistor Terminals
    G05316612Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  14. CHECK HARNESS AND CONNECTOR (F/PMP RELAY - FUEL PUMP RESISTER) 
    1. Check the harness and the connectors between the F/ PMP relay and the fuel pump resistor.
      1. Remove the F/PMP relay from the engine room J/B and R/B No. 2.
      2. Disconnect the fuel pump resistor connector.
      3. Measure the resistance according to the value (s) in the table below.

        Standard resistance (Check for open) 

        RESISTANCE SPECIFICATION

        Tester Connection Specified Condition
        F/PMP relay (4) - Fuel pump resistor (A40-2) Below 1 Ω
        F/PMP relay (3) - Fuel pump resistor (A40-1) Below 1 Ω

        Standard resistance (Check for short) 

        RESISTANCE SPECIFICATION

        Tester Connection Specified Condition
        Fuel pump relay (4) or Fuel pump resistor (A40-2) - Body ground 10 kΩ or higher
        Fuel pump relay (3) or Fuel pump resistor (A40-1) - Body ground 10 kΩ or higher
        Fig 11: Identifying Fuel Pump Resistor And F/PMP Relay Connector Terminals
        G05316613Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

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