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Home >> Lexus >> 2012 >> IS 250 Base, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Diagnostic Codes (P0630-U0101) & Circuit Tests) >> SFI System >> Circuit Tests >> Fuel Pump Control Circuit >> Procedure
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Fuel Pump Control Circuit: 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.

      Result

      Result Proceed to
      NG A
      OK B

    B → See step   12 

    A: Go to next step 

  2. PERFORM ACTIVE TEST USING TECHSTREAM (OPERATE C/OPN RELAY) 
    1. Connect 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 / 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 C/OPN relay.

      Result

      Result Proceed to
      NG A
      OK B

    B → See step   8 

    A: Go to next step 

  3. CHECK ECM POWER SOURCE CIRCUIT 
    1. Check ECM power source circuit. Refer to 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 R/B No. 2.
      Fig 1: Locating F/PMP Fuse
      GTY256793Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance of the F/PMP fuse.

      Standard resistance

      Below 1 Ω

    3. Reinstall the F/PMP fuse.

    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 R/B No. 2.
      Fig 2: Location of Integration Relay
      GTY264311Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      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)
    3. Reinstall the integration relay.

    NG → See step   15 

    OK: Go to next step 

  6. INSPECT INTEGRATION RELAY (C/OPN RELAY) 
    1. Remove the integration relay from the engine room R/B No. 2.
      Fig 3: Location of Integration Relay
      GTY264311Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      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)
    3. Reinstall the integration relay.

    NG → See step   16 

    OK: Go to next step 

  7. INSPECT ECM (FC VOLTAGE) 
    1. Turn the engine switch on (IG).
      Fig 4: Identifying E4 And A5 ECM Connector Terminals
      GTY127104Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard voltage

      Tester Connection Specified Condition
      A5-14 (FC) - E4-7 (E1) 11 to 14 V

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (ECM - C/OPN RELAY) 

    OK → See step   17 

  8. INSPECT F/PMP RELAY 
    1. Remove the F/PMP relay from the engine room R/B No. 2.
      Fig 5: Inspecting F/PMP Relay
      GTY104187Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection Specified Condition
      3 - 4 10 kΩ or higher
      3 - 4 Below 1 Ω
      (when battery voltage applied to terminals 1 and 2)
    3. Reinstall the F/PMP relay.

    NG → REPLACE F/PMP RELAY 

    OK: Go to next step 

  9. INSPECT FUEL PUMP 
    1. Inspect fuel pump. Refer to INSPECTION .

    NG → See step   18 

    OK: Go to next step 

  10. CHECK HARNESS AND CONNECTOR (FUEL PUMP - F/PMP RELAY AND BODY GROUND) 
    1. Check the harness and the connectors between the fuel pump and the F/PMP relay.
      1. Disconnect the Q14 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
        Q14-4 (Fuel pump) - 4 (F/PMP relay) Below 1 Ω

        Standard resistance (Check for short)

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

        Standard resistance (Check for open)

        Tester Connection Specified Condition
        Q14-5 (Fuel pump) - Body ground 10 kΩ or higher
      2. Reconnect the fuel pump connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  11. CHECK FUEL SYSTEM (C/OPN RELAY - F/PMP RELAY) 
    1. Remove the integration relay from the engine room 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
      2B-8 (Integration relay) - 1 (F/PMP relay) Below 1 Ω
      2B-8 (Integration relay) - 3 (F/PMP relay) Below 1 Ω
    4. Disconnect the fuel pump resistor connector.
    5. Measure the resistance according to the value(s) in the table below.

      Standard resistance (Check for short)

      Tester Connection Specified Condition
      2B-8 (Integration relay) or 1 (F/PMP relay) - Body ground 10 kΩ or higher
      2B-8 (Integration relay) or 3 (F/PMP relay) - Body ground 10 kΩ or higher
    6. Reinstall the relays.
    7. Reconnect the fuel pump resistor connector.

    NG → REPAIR OR REPLACE ENGINE ROOM RELAY BLOCK 

    OK → REPAIR OR REPLACE FUEL SYSTEM 

  12. INSPECT F/PMP RELAY 
    1. Remove the F/PMP relay from the engine room R/B No. 2.
      Fig 6: Inspecting F/PMP Relay
      GTY104187Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection Specified Condition
      3 - 4 10 kΩ or higher
      3 - 4 Below 1 Ω
      (when battery voltage applied to terminals 1 and 2)
    3. Reinstall the F/PMP relay.

    NG → REPLACE F/PMP RELAY 

    OK: Go to next step 

  13. INSPECT FUEL PUMP RESISTOR 
    1. Inspect the fuel pump resistor. Refer to INSPECTION .

    NG → See step   19 

    OK: Go to next step 

  14. CHECK HARNESS AND CONNECTOR (F/PMP RELAY - FUEL PUMP RESISTOR) 
    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 A40 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
        4 (F/PMP relay) - A40-2 (Fuel pump resistor) Below 1 Ω
        3 (F/PMP relay) - A40-1 (Fuel pump resistor) Below 1 Ω

        Standard resistance (Check for short)

        Tester Connection Specified Condition
        4 (Fuel pump relay) or A40-2 (Fuel pump resistor) - Body ground 10 kΩ or higher
        3 (Fuel pump relay) or A40-1 (Fuel pump resistor) - Body ground 10 kΩ or higher
      4. Reconnect the fuel pump resistor connector.
      5. Reinstall the F/PMP relay.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   20 

  15. REPLACE INTEGRATION RELAY. Refer to  REMOVAL 
  16. REPLACE INTEGRATION RELAY. Refer to  REMOVAL 
  17. REPLACE ECM. Refer to  REMOVAL 
  18. REPLACE FUEL PUMP. Refer to  REMOVAL 
  19. REPLACE FUEL PUMP RESISTOR. Refer to  REMOVAL 
  20. PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE 
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