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Home >> Nissan-Datsun >> 2006 >> Sentra SE-R >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Component Testing (Qr25DE) >> Fuel Pump >> Diagnostic Procedure
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Diagnostic Procedure

  1. CHECK OVERALL FUNCTION 
    1. Turn ignition switch ON.
    2. Pinch fuel feed hose with two fingers.

      Fuel pressure pulsation should be felt on the fuel hose for 1 second after ignition switch is turned ON. 

      3. Fig 1: Pinching Fuel Feed Hose
      G04192265Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: INSPECTION END 

    NG: GO TO  2.

  2. CHECK FUEL PUMP RELAY POWER SUPPLY CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect fuel pump relay.
    3. Turn ignition switch ON.
      Fig 2: Disconnecting Fuel Pump Relay
      G04192266Courtesy of NISSAN MOTOR CO., U.S.A.
    4. Check voltage between fuel pump relay terminals 1, 5 and ground with CONSULT-II or tester.

      Voltage: Battery voltage 

      5. Fig 3: Checking Voltage Between Fuel Pump Relay Terminals 1, 5 And Ground
      G04192267Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: GO TO  4.

    NG: GO TO  3.

  3. DETECT MALFUNCTIONING PART 

    Check the following.

    • Fuse block (J/B) connector B4
    • 10A fuse
    • 15A fuse
    • Harness for open or short between fuse and fuel pump relay

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

  4. CHECK FUEL PUMP POWER SUPPLY AND GROUND CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Disconnect "fuel level sensor unit and fuel pump" harness connector.
      3. Fig 4: Disconnecting Fuel Level Sensor Unit & Fuel Pump Harness Connector
      G04192268Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check harness continuity between the following; fuel pump relay terminal 3 and fuel pump terminal 1, fuel pump terminal 3 and ground.

      Refer to WIRING DIAGRAM .

      Continuity should exist. 

    4. Also check harness for short to ground and short to power.

    OK or NG 

    OK: GO TO  5.

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

  5. CHECK FUEL PUMP RELAY OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Disconnect ECM harness connector.
    2. Check harness continuity between ECM terminal 113 [without NVIS (NATS)] or 114 [with NVIS (NATS)] and fuel pump relay terminal 2.

      Refer to WIRING DIAGRAM .

      Continuity should exist. 

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

    OK or NG 

    OK: GO TO  7.

    NG: GO TO  6.

  6. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors B3, M16
    • Harness connectors M58, F26
    • Harness for open or short between ECM and fuel pump relay

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

  7. CHECK FUEL PUMP RELAY 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO  8.

    NG: Replace fuel pump relay.

  8. CHECK FUEL PUMP 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO  9.

    NG: Replace fuel pump.

  9. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

    : INSPECTION END 

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