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Home >> Nissan-Datsun >> 2021 >> Sentra S >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System (2 Of 2) >> Components/Circuit Diagnosis >> High Pressure Fuel Pump >> Diagnosis Procedure
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Diagnosis Procedure

  1. CHECK FUSE 
    1. Turn ignition switch OFF.
    2. Check that the following fuse is not blowing.

      Fuse No.

      Capacity

      No. 68

      10 A

    Is the fuse blown (open)?

    YES

    Replace the fuse after repairing the applicable circuit.

    NO

    GO TO 2.

  2. CHECK HIGH PRESSURE FUEL PUMP POWER SUPPLY 
    1. Turn ignition switch ON.
    2. Check the voltage between ECM harness connector and ground.

      +

      -

      Voltage

      ECM

      Connector

      Terminal

      F25

      66

      Ground

      Battery voltage

    Is the inspection result normal?

    YES

    GO TO 9.

    NO

    GO TO 3.

  3. CHECK HIGH PRESSURE FUEL PUMP POWER SUPPLY CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Disconnect high pressure fuel pump relay harness connector.
    4. Check the continuity between ECM harness connector and high pressure fuel pump relay harness connector.

      ECM

      High pressure fuel pump relay

      Continuity

      Connector

      Terminal

      Connector

      Terminal

      F25

      66

      F61

      2

      Existed
    5. Also check harness for short to ground and short to power.

    Is the inspection result normal?

    YES

    GO TO 4.

    NO

    Repair or replace malfunctioning part.

  4. CHECK HIGH PRESSURE FUEL PUMP RELAY POWER SUPPLY (CONTACT SIDE) 

    Check the voltage between high pressure fuel pump relay harness connector and ground.

    +

    -

    Voltage

    High pressure fuel pump relay

    Connector

    Terminal

    F61

    1

    Ground

    Battery voltage

    Is the inspection result normal?

    YES

    GO TO 5.

    NO

    Perform the trouble diagnosis for power supply circuit.

  5. CHECK HIGH PRESSURE FUEL PUMP RELAY POWER SUPPLY (EXCITATION COIL SIDE) 
    1. Install all removed parts.
    2. Turn ignition switch ON.
    3. Check the voltage between high pressure fuel pump relay harness connector and ground.

      +

      -

      Voltage

      High pressure fuel pump relay

      Connector

      Terminal

      F61

      3

      Ground

      Battery voltage

    Is the inspection result normal?

    YES

    GO TO 7.

    NO

    GO TO 6.

  6. CHECK HIGH PRESSURE FUEL PUMP RELAY POWER SUPPLY CIRCUIT (EXCITATION COIL SIDE) 
    1. Turn ignition switch OFF.
    2. Disconnect IPDM E/R harness connector.
    3. Disconnect high pressure fuel pump relay harness connector.
    4. Check the continuity between IPDM E/R harness connector and high pressure fuel pump relay harness connector.

      IPDM E/R

      High pressure fuel pump relay

      Continuity

      Connector

      Terminal

      Connector

      Terminal

      F96

      73

      F61

      3

      Existed
    5. Also check harness for short to ground and short to power.

    Is the inspection result normal?

    YES

    Perform the trouble diagnosis for power supply circuit.

    NO

    Repair or replace malfunctioning part.

  7. CHECK HIGH PRESSURE FUEL PUMP RELAY GROUND CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect high pressure fuel pump relay harness connector.
    3. Check the continuity between high pressure fuel pump relay harness connector and ground.

      High pressure fuel pump relay

      --

      Continuity

      Connector

      Terminal

      F61

      4

      Ground

      Existed
    4. Also check harness for short to ground.

    Is the inspection result normal?

    YES

    GO TO 8.

    NO

    Repair or replace malfunctioning part.

  8. CHECK HIGH PRESSURE FUEL PUMP RELAY 

    Refer to Component Inspection .

    Is the inspection result normal?

    YES

    Check intermittent incident. Refer to Intermittent Incident .

    NO

    Replace high pressure fuel pump relay.

  9. CHECK ECM GROUND CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Check the continuity between ECM harness connector and ground.

      ECM

      --

      Continuity

      Connector

      Terminal

      F24

      5

      Ground

      Existed

      65

      F25

      69

      E16

      157

      159

      162
    4. Also check harness for short to power.

    Is the inspection result normal?

    YES

    GO TO 10.

    NO

    Repair or replace malfunctioning part.

  10. CHECK HIGH PRESSURE FUEL PUMP CIRCUIT 
    1. Disconnect high pressure fuel pump relay harness connector.
    2. Check the continuity between ECM harness connector and high pressure fuel pump harness connector.

      ECM

      High pressure fuel pump

      Continuity

      Connector

      Terminal

      Connector

      Terminal

      F25

      67

      F32

      1

      Existed

      68

      2
    3. Also check harness for short to ground and short to power.

    Is the inspection result normal?

    YES

    GO TO 11.

    NO

    Repair or replace malfunctioning part.

  11. CHECK HIGH PRESSURE FUEL PUMP 

    Refer to Component Inspection .

    Is the inspection result normal?

    YES

    GO TO 12.

    NO

    Replace high pressure fuel pump. Refer to Removal and Installation .

  12. CHECK HIGH PRESSURE FUEL PUMP INSTALLATION 
    1. Turn ignition switch OFF.
    2. Check high pressure fuel pump for improper attachment or looseness.

    Is the inspection result normal?

    YES

    GO TO 13.

    NO

    Repair or replace malfunctioning part.

  13. CHECK CAMSHAFT 
    1. Remove camshaft. Refer to Removal and Installation .
    2. Check camshaft. Refer to Inspection .

    Is the inspection result normal?

    YES

    Check intermittent incident. Refer to Intermittent Incident .

    NO

    Replace camshaft. Refer to Removal and Installation .

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