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Home >> Infiniti >> 2004 >> Q45 >> Repair and Diagnosis >> Engine Performance >> Engine Control System >> Fuel Pump Circuit >> Diagnostic Procedure >> 4. Check Fuel Pump Power Supply And Ground Circuit For Open And Short
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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. Disconnect dropping resistor harness connector.
    Fig 1: Locating Fuel Pump Control Module
    G00761388Courtesy of NISSAN MOTOR CO., U.S.A.
  4. Check harness continuity between the following;

    fuel pump relay terminal 5 and fuel pump terminal 3,

    fuel pump terminal 1 and dropping resistor terminal 2,

    dropping resistor terminal 1 and ground.

    Refer to Wiring Diagram.

    1. Continuity should exist. 
  5. Also check harness for short to ground and short to power.

OK or NG 

OK: GO TO 6.

NG: GO TO 5.