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Home >> Infiniti >> 2013 >> FX50 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - System Component Testing >> Fuel Pump >> Diagnosis Procedure
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Diagnosis Procedure

  1. CHECK GROUND CONNECTION 
    1. Turn ignition switch OFF.
    2. Check ground connection M95. Refer to Ground Inspection in "CIRCUIT INSPECTION ".

      Is the inspection result normal? 

      YES: GO TO 2.

      NO: Repair or replace ground connection.

  2. CHECK FPCM POWER SUPPLY CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect FPCM harness connector.
    3. Turn ignition switch ON.
    4. Check the voltage between FPCM harness connector and ground.
      FPCM Ground Voltage
      Connector Terminal
      B31 10 Ground Battery voltage

      Is the inspection result normal? 

      YES: GO TO  4.

      NO: GO TO 3.

  3. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors B3, E121
    • 15 A fuse (No. 41)
    • Harness for open or short between FPCM and IPDM E/R

      : Repair open circuit, short to ground or short to power in harness or connectors.

  4. CHECK FPCM GROUND CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Check the continuity between FPCM harness connector and ground.
      FPCM Ground Continuity
      Connector Terminal
      B31 5 Ground Existed
    3. Also check harness for short to power.

      Is the inspection result normal? 

      YES: GO TO 5.

      NO: Repair open circuit or short to power in harness or connectors.

  5. CHECK FPCM INPUT AND OUTPUT CIRCUITS FOR OPEN AND SHORT 
    1. Disconnect ECM harness connector.
    2. Check the continuity between FPCM harness connector and ECM harness connector.
      FPCM ECM Continuity
      Connector Terminal Connector Terminal
      B31 8 M160 125 Existed
      9 112
    3. Also check harness for short to ground and short to power.

      Is the inspection result normal? 

      YES: GO TO  7.

      NO: GO TO 6.

  6. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors B1, M7
    • Harness for open or short between FPCM and ECM

      : Repair open circuit, short to ground or short to power in harness or connectors.

  7. CHECK FUEL PUMP CONTROL CIRCUIT FOR OPEN AND SHORT 
    1. Disconnect "fuel level sensor unit and fuel pump (main)" harness connector.
    2. Check the continuity between FPCM harness connector and "fuel level sensor unit and fuel pump (main)" harness connector.
      FPCM Fuel level sensor unit and fuel pump (main) Continuity
      Connector Terminal Connector Terminal
      B31 6 B22 3 Existed
      7 1
    3. Also check harness for short to ground and short to power.

      Is the inspection result normal? 

      YES: GO TO 8.

      NO: Repair open circuit, short to ground or short to power in harness or connectors.

  8. CHECK FUEL PUMP 

    Refer to "COMPONENT INSPECTION ".

    Is the inspection result normal? 

    YES: GO TO 9.

    NO: Replace fuel pump. Refer to "EXPLODED VIEW ".

  9. CHECK FPCM 

    Refer to "COMPONENT INSPECTION ".

    Is the inspection result normal? 

    YES: GO TO 10.

    NO: Replace FPCM.

  10. CHECK INTERMITTENT INCIDENT 

    Refer to "INTERMITTENT INCIDENT ".

    : INSPECTION END

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