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Home >> Infiniti >> 2021 >> Q50 Pure, AWD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System (DTCS) (4 Of 6) >> Engine (ECM) >> DTC P1220: Fuel Pump Control Module (FPCM) >> DTC Diagnosis Procedure >> VR30DDTT engine
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VR30DDTT engine

  1. CHECK FUSE 
    1. Turn ignition switch OFF.
    2. Disconnect 15 A fuse (No. 52) from IPDM E/R.
    3. Check 15 A fuse for blown.

    Is the fuse blown (open)?

    YES

    Replace the fuse. [Check the power supply if fuse is blown (open) again.]

    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

      B11

      6

      Ground

      Battery voltage

    Is the inspection result normal?

    YES

    GO TO 4.

    NO

    GO TO 3.

  3. CHECK FPCM POWER SUPPLY CIRCUIT FOR OPEN AND SHORT 
    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

      B11

      6

      E120

      15

      Existed

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

    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 FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Check the continuity between FPCM harness connector and ground.

      +

      -

      Continuity

      FPCM

      Connector

      Terminal

      B11

      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 FOR OPEN AND SHORT 
    1. Disconnect ECM harness connector.
    2. Check the continuity between FPCM harness connector and ECM harness connector.

      +

      -

      Continuity

      FPCM

      ECM

      Connector

      Terminal

      Connector

      Terminal

      B11

      4

      E152

      182

      Existed

      5

      188

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

    Is the inspection result normal?

    YES

    GO TO 6.

    NO

    Repair or replace error-detected parts.

  6. CHECK FUEL PUMP CONTROL CIRCUIT FOR OPEN AND SHORT 
    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.

      +

      -

      Continuity

      FPCM

      Fuel level sensor unit and fuel pump (main)

      Connector

      Terminal

      Connector

      Terminal

      B11

      1

      B101

      5

      Existed

      2

      6

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

    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 & Installation .