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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.
      CONNECTOR TERMINAL VOLTAGE CHART

      ECM Voltage
      + -
      Connector Terminal Connector Terminal
      F105 22 M9 128 Battery voltage
      Fig 1: Checking Voltage Between ECM Harness Connector Terminals
      G06306804Courtesy of NISSAN MOTOR CO., U.S.A.

      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.

    CONNECTOR TERMINAL VOLTAGE CHART

    IPDM E/R Ground Voltage
    Connector Terminal
    E8 40 Ground Battery voltage
    Fig 2: Checking Voltage Between IPDM E/R Terminal 40 And Ground
    G04915864Courtesy of NISSAN MOTOR CO., U.S.A.

    Is the inspection result normal? 

    YES: GO TO 3.

    NO: GO TO  13.

  3. DETECT MALFUNCTIONING PART

    Check the following.

    • Harness connectors E11, F2
    • Harness for open or short between IPDM E/R and ECM

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

  4. CHECK FUEL PUMP POWER SUPPLY CIRCUIT-II
    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.
      Fig 3: Checking Voltage Between Fuel Level Sensor Unit And Fuel Pump Terminal 1 And Ground
      G04895195Courtesy of NISSAN MOTOR CO., U.S.A.
      CONNECTOR TERMINAL VOLTAGE CHART

      Fuel level sensor unit and fuel pump (main) Ground Voltage
      Connector Terminal
      B433 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. 81) from IPDM E/R.
    3. Check 15 A fuse.

      Is the inspection result normal? 

      YES: GO TO 6.

      NO: Replace 15 A fuse.

  6. CHECK FUEL PUMP POWER SUPPLY CIRCUIT-III
    1. Disconnect IPDM E/R harness connector E8.
    2. Check the continuity between IPDM E/R harness connector and "fuel level sensor unit and fuel pump (main)" harness connector.
      CONNECTOR TERMINAL CONTINUITY CHART

      IPDM E/R Fuel level sensor unit and fuel pump (main) Continuity
      Connector Terminal Connector Terminal
      E8 39 B433 1 Existed
    3. Also check harness for short to ground and short to power.

      Is the inspection result normal? 

      YES: GO TO  8.

      NO: GO TO 7.

  7. DETECT MALFUNCTIONING PART

    Check the following.

    • Harness connectors B4, E106
    • Harness connectors B65, B434
    • IPDM E/R harness connector E8
    • 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-I
    1. Turn ignition switch OFF.
    2. Disconnect dropping resistor harness connector.
    3. Check the continuity between "fuel level sensor unit and fuel pump (main)" harness connector and dropping resistor.
      CONNECTOR TERMINAL CONTINUITY CHART

      Fuel level sensor unit and fuel pump (main) Dropping resistor Continuity
      Connector Terminal Connector Terminal
      B433 3 B112 2 Existed
    4. Also check harness for short to power.

      Is the inspection result normal? 

      YES: GO TO  10.

      NO: GO TO 9.

  9. DETECT MALFUNCTIONING PART

    Check the following.

    • Harness connectors B65, B434
    • Harness for open or short between "fuel level sensor unit and fuel pump (main)" and dropping resistor

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

  10. CHECK FUEL PUMP GROUND CIRCUIT-II
    1. Check the continuity between dropping resistor and ground.
      CONNECTOR TERMINAL CONTINUITY CHART

      Dropping resistor Ground Continuity
      Connector Terminal
      B112 1 Ground Existed
    2. Also check harness for short to power.

      Is the inspection result normal? 

      YES: GO TO 11.

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

  11. CHECK DROPPING RESISTOR

    Refer to "COMPONENT INSPECTION (DROPPING RESISTOR) ".

    Is the inspecting result normal? 

    YES: GO TO 12.

    NO: Replace dropping resistor.

  12. CHECK FUEL PUMP

    Refer to "COMPONENT INSPECTION (FUEL PUMP) ".

    Is the inspection result normal? 

    YES: GO TO 13.

    NO: Replace fuel pump.

  13. CHECK INTERMITTENT INCIDENT

    Refer to "DESCRIPTION ".

    Is the inspection result normal? 

    YES: Replace IPDM E/R.

    NO: Repair or replace harness or connectors.

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