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Home >> Infiniti >> 2004 >> Q45 >> Repair and Diagnosis >> Engine Performance >> Engine Control System >> DTC P1220: Fuel Pump Control Module (FPCM) >> Diagnostic Procedure >> 5. Check FPCM Ground Circuit-II For Open And Short
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5. Check FPCM Ground Circuit-II For Open And Short

  1. Disconnect "fuel level sensor unit and fuel pump" harness connector.
  2. Disconnect dropping resistor harness connector.
  3. Check harness continuity between the following;

    "fuel level sensor unit and fuel pump" terminal 1 and dropping resistor terminal 2,

    FPCM terminal 4 and dropping resister terminal 2.

    Refer to Wiring Diagram.

    1. Continuity should exist. 
  4. Check harness continuity between the following;

    FPCM terminal 4 and ground, "fuel level sensor and fuel pump" terminal 1 and ground.

    Refer to Wiring Diagram.

    1. Continuity should not exist. 
  5. Also check harness for short to power.

OK or NG 

OK: GO TO 7.

NG: GO TO 6.