Diagnostic Procedure

CHECK AIR FUEL RATIO (A/F) SENSOR 1 POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Loosen and retighten engine ground screws.
  
  Fig 1: Identifying Engine Ground
  Courtesy of NISSAN MOTOR CO., U.S.A.
3. Disconnect air fuel ratio (A/F) sensor 1 harness connector.
4. Turn ignition switch ON.
  
  Fig 2: Disconnecting Air Fuel Ratio (A/F) Sensor 1 Harness Connector
  Courtesy of NISSAN MOTOR CO., U.S.A.
5. Check voltage between A/F sensor 1 terminal 3 and ground with CONSULT-II or tester.
  
  Fig 3: Checking Voltage Between A/F Sensor 1 Terminal 3 & Ground
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  Voltage: Battery voltage
OK or NG
1. OK: GO TO 3.
2. NG: GO TO 2.
DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors M19, E108
- Harness connectors E10, F48
- Fuse block (J/B) connector M1
- 15A fuse
- Harness for open or short between A/F sensor 1 and fuse
  Repair or replace harness or connectors.
CHECK A/F SENSOR 1 HEATER OUTPUT SIGNAL CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 2 and A/F sensor 1 terminal 4. Refer to WIRING DIAGRAM .
  Continuity should exist.
4. Also check harness for short to power.
OK or NG
1. OK: GO TO 4.
2. NG: Repair open circuit or short to ground or short to power in harness or connectors.
CHECK A/F SENSOR 1 HEATER
Refer to "COMPONENT INSPECTION ".

OK or NG
1. OK: GO TO 5.
2. NG: Replace A/F sensor 1.
CHECK INTERMITTENT INCIDENT
Perform "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

OK or NG
1. OK: Replace A/F sensor 1.
2. NG: Repair or replace.