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Home >> Infiniti >> 2012 >> G25 Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Component Testing >> Fuel Pump >> Diagnosis Procedure
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Diagnosis Procedure

  1. CHECK FUEL PUMP POWER SUPPLY CIRCUIT-I
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Turn ignition switch ON.
    4. Check the voltage between ECM harness connector and ground.
      ECM Ground Voltage
      Connector Terminal
      F101 22 Ground Battery voltage

      Is the inspection result normal? 

      YES: GO TO  4.

      NO: GO TO 2.

  2. CHECK FUEL PUMP POWER SUPPLY CIRCUIT-II

    Check the voltage between IPDM E/R harness connector and ground.

    IPDM E/R Ground Voltage
    Connector Terminal
    E7 77 Ground Battery voltage

    Is the inspection result normal? 

    YES: GO TO 3.

    NO: GO TO  10.

  3. DETECT MALFUNCTIONING PART

    Check the following.

    • Harness connectors E25, F30
    • Harness connectors F104, F105
    • Harness for open or short between IPDM E/R and ECM

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

  4. CHECK FUEL PUMP POWER SUPPLY CIRCUIT-III
    1. Turn ignition switch OFF.
    2. Reconnect all harness connectors disconnected.
    3. Disconnect "fuel level sensor unit and fuel pump (main)" harness connector.
    4. Turn ignition switch ON.
    5. Check the voltage between "fuel level sensor unit and fuel pump (main)" harness connector and ground.
      Fuel level sensor unit and fuel pump (main) Ground Voltage
      Connector Terminal
      B22 1 Ground Battery voltage should exist for 1 second after ignition switch is turned ON.

      Is the inspection result normal? 

      YES: GO TO  8.

      NO: GO TO 5.

  5. CHECK 15 A FUSE
    1. Turn ignition switch OFF.
    2. Disconnect 15 A fuse (No. 41) from IPDM E/R.
    3. Check 15 A fuse.

      Is the inspection result normal? 

      YES: GO TO 6.

      NO: Replace fuse.

  6. CHECK FUEL PUMP POWER SUPPLY CIRCUIT-IV
    1. Disconnect IPDM E/R harness connector.
    2. Check the continuity between IPDM E/R harness connector and "fuel level sensor unit and fuel pump (main)" harness connector.
      IPDM E/R Fuel level sensor unit and fuel pump (main) Continuity
      Connector Terminal Connector Terminal
      E5 13 B22 1 Existed
    3. Also check harness for short to ground and short to power.

      Is the inspection result normal? 

      YES: GO TO  10.

      NO: GO TO 7.

  7. DETECT MALFUNCTIONING PART

    Check the following.

    • Harness connectors E117, B9
    • IPDM E/R harness connector E5
    • Harness for open or short between IPDM E/R and "fuel level sensor unit and fuel pump (main)"

      Repair open circuit or short to power in harness or connectors.

  8. CHECK FUEL PUMP GROUND CIRCUIT
    1. Turn ignition switch OFF.
    2. Check the continuity between "fuel level sensor unit and fuel pump (main)" harness connector and ground.
      Fuel level sensor unit and fuel pump (main) Ground Continuity
      Connector Terminal
      B22 3 Ground Existed
    3. Also check harness for short to power.

      Is the inspection result normal? 

      YES: GO TO 9.

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

  9. CHECK FUEL PUMP

    Refer to "COMPONENT INSPECTION ".

    Is the inspection result normal? 

    YES: GO TO 10.

    NO: Replace fuel pump. Refer to "REMOVAL AND INSTALLATION ".

  10. CHECK INTERMITTENT INCIDENT

    Refer to "INTERMITTENT INCIDENT ".

    Is the inspection result normal? 

    YES: Replace IPDM E/R. Refer to "REMOVAL AND INSTALLATION ".

    NO: Repair or replace harness or connectors.

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