Diagnostic Procedure

CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten two ground screws on the body. Refer to "GROUND INSPECTION ".
  
  Fig 1: Loosening Ground Screws On Body
  Courtesy of NISSAN MOTOR CO., U.S.A.
OK or NG
1. OK: GO TO 2.
2. NG: Repair or replace ground connections.
CHECK FUEL TANK TEMPERATURE SENSOR POWER SUPPLY CIRCUIT
1. Disconnect "fuel level sensor unit and fuel pump" harness connector.
2. Turn ignition switch ON.
  
  Fig 2: Identifying Fuel Level Sensor Unit And Fuel Pump Harness Connector
  Courtesy of NISSAN MOTOR CO., U.S.A.
3. Check voltage between "fuel level sensor unit and fuel pump" terminal 4 and ground with CONSULT-II or tester.
  Voltage: Approximately 5V
  
  Fig 3: Identifying Voltage Between Terminal No. 4 & Ground
  Courtesy of NISSAN MOTOR CO., U.S.A.
OK or NG
1. OK: GO TO 4.
2. NG: GO TO 3.
DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors M72, F102
- Harness connectors B1, M12
- Harness for open or short between ECM and "fuel level sensor unit and fuel pump"
  Repair open circuit or short to ground or short to power in harness or connector.
CHECK FUEL TANK TEMPERATURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Check harness continuity between "fuel level sensor unit and fuel pump" terminal 5 and ground.
  Refer to WIRING DIAGRAM .
  
  Continuity should exist.
3. Also check harness for short to power.
OK or NG
1. OK: GO TO 6.
2. NG: GO TO 5.
DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors B1, M12
- Harness for open or short between "fuel level sensor unit and fuel pump" and ground.
  Repair open circuit or short to power in harness or connector.
CHECK FUEL TANK TEMPERATURE SENSOR
Refer to "COMPONENT INSPECTION ".

OK or NG
1. OK: GO TO 7.
2. NG: Replace fuel level sensor unit.
CHECK INTERMITTENT INCIDENT
Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

INSPECTION END