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Home >> Infiniti >> 2016 >> Q50 Base, RWD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System (DTC/Circuit Diagnosis) (Except Hybrid) (5 Of 5) >> DTC/Circuit Diagnosis >> DTC P2540: Fuel Pressure Sensor >> Fuel Pump Control Module (FPCM) >> Diagnosis Procedure >> Diagnostic Test
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Diagnostic Test

  1. COMPONENT FUNCTION CHECK

    G-20 With CONSULT

    1. Turn ignition switch OFF.
    2. Start the engine and let it idle.
    3. On CONSULT screen, select "FPCM" >> "DATA MONITOR" >> "FUEL PRESSURE".
    4. Check that the indicated value is between 400 kPa (4 bar, 4.08 kg/cm2 , 58 psi) and 670 kPa (6.7 bar, 6.834 kg/cm2 , 97.15 psi).

    Is the inspection result normal?

    YES 

    INSPECTION END

    NO 

    GO TO STEP 2  .

  2. CHECK FUEL PRESSURE SENSOR POWER SUPPLY

    1. Turn ignition switch OFF.
    2. Disconnect fuel pressure sensor harness connector.
    3. Turn ignition switch ON.
    4. Check the voltage between fuel pressure sensor harness connector terminals.
      Fuel pressure sensor Voltage
      (Approx.)
      Connector + -
      Terminal
      E199 1 2 5 V

    Is the inspection result normal?

    YES 

    GO TO STEP 5. 

    NO 

    GO TO STEP 3  .

  3. CHECK FUEL PRESSURE SENSOR POWER SUPPLY AND GROUND CIRCUIT

    1. Turn ignition switch OFF.
    2. Disconnect FPCM harness connector and fuel pressure sensor harness connector.
    3. Check the continuity between FPCM harness connector and fuel pressure sensor harness connector.
      + - Continuity
      FPCM Fuel pressure sensor
      Connector Terminal Connector Terminal
      B134 6 E199 2 Existed
      8 1
    4. Also check harness for short to ground.

    Is the inspection result normal?

    YES 

    GO TO STEP 4  .

    NO 

    Repair or replace error-detected parts.

  4. CHECK FPCM POWER SUPPLY AND GROUND CIRCUIT

    Check FPCM power supply and ground circuit. Refer to DIAGNOSIS PROCEDURE .

    Is the inspection result normal?

    YES 

    Replace FPCM. Refer to DIAGNOSIS PROCEDURE .

    NO 

    Repair or replace error-detected parts.

  5. CHECK FUEL PRESSURE SENSOR SIGNAL CIRCUIT

    1. Turn ignition switch OFF.
    2. Disconnect FPCM harness connector and fuel pressure sensor harness connector.
    3. Check the continuity between FPCM harness connector and fuel pressure sensor harness connector.
      + - Continuity
      FPCM Fuel pressure sensor
      Connector Terminal Connector Terminal
      B134 7 E199 3 Existed
    4. Also check harness for short to ground.

    Is the inspection result normal?

    YES 

    Replace fuel pressure sensor.

    NO 

    Repair or replace error-detected parts.