Diagnostic Procedure

CHECK FUEL TANK TEMPERATURE SENSOR POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect fuel level sensor unit harness connector.
3. Turn ignition switch ON.
  
  Fig 1: Locating Fuel Level Sensor Unit Harness Connector
  Courtesy of NISSAN MOTOR CO., U.S.A.
4. Check voltage between fuel level sensor unit terminal T and engine ground with CONSULT-II or tester.
  Voltage: Approximately 5V
OK or NG
1. OK: GO TO 3.
2. NG: GO TO 2.
  
  Fig 2: Checking Voltage Between Fuel Level Sensor Unit Terminal T And Engine Ground
  Courtesy of NISSAN MOTOR CO., U.S.A.
DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors C1, M67
- Harness connectors M81, F36
- Harness for open or short between ECM and fuel tank temperature sensor
: Repair 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 terminal E and body ground. Refer to WIRING DIAGRAM .
  Continuity should exist.
3. Also check harness for short to power.
OK or NG
1. OK: GO TO 5.
2. NG: GO TO 4.
DETECT MALFUNCTIONING PART
Check the following.
- Harness for open between fuel tank temperature sensor and body ground
- Harness connectors C1, M67
: Repair open circuit or short to power in harness or connectors.
CHECK FUEL TANK TEMPERATURE SENSOR
1. Remove fuel level sensor unit.
2. Check resistance fuel level sensor unit terminals T and E by heating with hot water or heat gun as shown in the figure.
  
  Fig 3: Checking Fuel Tank Temperature Sensor
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  Fig 4: Reference Data
  Courtesy of NISSAN MOTOR CO., U.S.A.
OK or NG
1. OK: GO TO 6.
2. NG: Replace fuel tank temperature sensor.
CHECK INTERMITTENT INCIDENT
Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

: INSPECTION END