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Home >> Infiniti >> 2024 >> QX80 Premium Select, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (DTCS) (2 Of 4) >> Engine (ECM) >> DTC P025B: Fuel Pump Module A >> DTC Diagnosis Procedure
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DTC Diagnosis Procedure

  1. CHECK FUSE 
    1. Turn ignition switch OFF.
    2. Pull out 15 A fuse (No. 60) from IPDM E/R.
    3. Check that 15 A fuse is not blowing.

    Is the fuse blown (open)?

    YES>>

    Replace the fuse after repairing the applicable circuit.

    NO>>

    GO TO 2.

  2. CHECK FPCM POWER SUPPLY 
    1. Turn ignition switch OFF.
    2. Disconnect FPCM harness connector.
    3. Turn ignition switch ON.
    4. Check the voltage between FPCM harness connector and ground.
      + - Voltage
      FPCM
      Connector Terminal
      B1 6 Ground Battery voltage

    Is the inspection result normal?

    YES>>

    GO TO 4.

    NO>>

    GO TO 3.

  3. CHECK FPCM POWER SUPPLY CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect IPDM E/R harness connector.
    3. Check the continuity between FPCM harness connector and IPDM E/R harness connector.
      FPCM IPDM E/R Continuity
      Connector Terminal Connector Terminal
      B1 6 E15 54 Existed
    4. Also check harness for short to power and short to ground.

    Is the inspection result normal?

    YES>>

    Perform trouble diagnosis for power supply circuit.

    NO>>

    Repair or replace error-detected parts.

  4. CHECK FPCM GROUND CIRCUIT 
    1. Turn ignition switch OFF.
    2. Check the continuity between FPCM harness connector and ground.
      FPCM - Continuity
      Connector Terminal
      B1 3 Ground Existed
    3. Also check harness for short to power.

    Is the inspection result normal?

    YES>>

    GO TO 5.

    NO>>

    Repair or replace error-detected parts.

  5. CHECK FPCM INPUT AND OUTPUT CIRCUIT 
    1. Disconnect ECM harness connector.
    2. Check the continuity between FPCM harness connector and ECM harness connector.
      FPCM ECM Continuity
      Connector Terminal Connector Terminal
      B1 4 E20 130 Existed
      5 136
    3. Also check harness for short to power and short to ground.

    Is the inspection result normal?

    YES>>

    GO TO 6.

    NO>>

    Repair or replace error-detected parts.

  6. CHECK FUEL PUMP CONTROL CIRCUIT 
    1. Disconnect "fuel level sensor unit and fuel pump (main)" harness connector.
    2. Check the continuity between FPCM harness connector and "fuel level sensor unit and fuel pump (main)" harness connector.
      FPCM Fuel level sensor unit and fuel pump Continuity
      Connector Terminal Connector Terminal
      B1 1 C5 1 Existed
      2 3
    3. Also check harness for short to power and short to ground.

    Is the inspection result normal?

    YES>>

    GO TO 7.

    NO>>

    Repair or replace error-detected parts.

  7. CHECK FPCM 

    Refer to Component Inspection . Is the inspection result normal?

    YES>>

    INSPECTION END

    NO>>

    Replace FPCM. Refer to FUEL PUMP CONTROL MODULE (FPCM) : Removal and Installation .

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