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Home >> Lexus >> 2008 >> IS 350 >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System (2GR-FSE) - System And Component Testing, On-Vehicle Inspection, Removal, Inspection & Installation >> Fuel Pump Control Circuit >> Inspection Procedure
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Inspection Procedure

  1. CHECK 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 TECHSTREAM (OPERATE CIRCUIT OPENING RELAY) 
    1. Connect Techstream to the DLC3.
    2. Turn the engine switch on (IG) and turn Techstream on.
    3. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the fuel Pump / Speed.
    4. Check the operation of the relay while operating it using Techstream.

      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 
    1. Check the ECM power source circuit (See ECM POWER SOURCE CIRCUIT ).

      Standard voltage: 

      9 to 14 V 

      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 R/B No. 2.
    2. Measure the resistance of the F/PMP fuse.

      Standard resistance: 

      Below 1 Ω 

      Fig 1: Identifying F/PMP Fuse
      G05316169Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      NG: REPLACE F/PMP 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 No. 2.
    2. Measure the resistance according to the value(s) in the table below.

    Standard resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Specified Condition
    2B-3 - 2C-1 10 kΩ or higher
    2B-3 - 2C-1 Below 1 Ω (when battery voltage applied to terminals 2B-3 and 2B-2)
    Fig 2: Identifying Integration Relay
    G05822798Courtesy 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 No. 2.
    2. Measure the resistance according to the value(s) in the table below.

    Standard resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    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
    G05315933Courtesy 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 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Specified Condition
    FC (A5-14) - E1 (E4-7) 9 to 14 V
    Fig 4: Identifying Terminals Of ECM Connector
    G05316172Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: REPLACE ECM 

    NG: CHECK AND REPAIR HARNESS AND CONNECTOR (ECM - C/OPN RELAY) 

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

    Standard resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    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 Terminals Of F/PMP Relay
    G05285125Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE F/PMP RELAY 

  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.
    • Fig 6: Identifying Terminals Of Fuel Pump
      G05822802Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE FUEL PUMP 

    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 R/B No. 2.
      3. Measure the resistance according to the value(s) in the table below.

      Standard resistance (Check for open) 

      TESTER CONNECTION SPECIFIED CONDITION CHART

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

      Standard resistance (Check for short) 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      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) 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Specified Condition
    Fuel pump (Q14-5) - Body ground 10 kΩ or higher
    Fig 7: Identifying Terminals Of Q14 Fuel Pump
    G05822803Courtesy 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 R/B No. 2.
    3. Measure the resistance according to the value(s) in the table below.

    Standard resistance (Check for open) 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    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) 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    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 Terminals Of Integration Relay
    G05822804Courtesy 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 R/B No. 2.
    2. Measure the resistance according to the value(s) in the table below.

    Standard resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    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 Terminals Of F/PMP Relay
    G05285125Courtesy 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.
      Fig 10: Measuring Resistance Of Fuel Pump Resistor Terminals
      G04962581Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard resistance: 

      0.30 to 0.34 Ω at 20°C (68°F) 

      NG: REPLACE FUEL PUMP RESISTER 

  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 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) 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    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) 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    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 Terminals Of A40 Fuel Pump Resistor Connector
    G05822807Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR