Diagnostic Procedure

1. Turn ignition switch OFF.
2. Loosen and retighten ground three screws on the body. Refer to GROUND INSPECTION  .
   Fig 1: Checking Ground Connections

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OK or NG 

1. OK: GO TO 2.
2. NG: Repair or replace ground connections.

1. Disconnect air fuel ratio (A/F) sensor 1 harness connector.
   Fig 2: Checking Air Fuel Ratio (A/F) Sensor 1 Power Supply Circuit

   Courtesy of NISSAN MOTOR CO., U.S.A.
2. Turn ignition switch ON.
3. Check voltage between A/F sensor 1 terminal 3 and ground with CONSULT-II or tester.
   Fig 3: Check Voltage Between A/F Sensor 1 Terminal 3 And Ground

   Courtesy of NISSAN MOTOR CO., U.S.A.
   1. Voltage: Battery voltage 

OK or NG 

1. OK: GO TO  4 .
2. NG: GO TO 3.

Check the following.

• Harness connectors E5, F14
• IPDM E/R harness connector E122
• 15A fuse
• Harness for open or short between A/F sensor 1 and fuse
  1. Repair or replace harness or connectors.

1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between the following terminals.

   Refer to WIRING DIAGRAM  .

   Fig 4: Checking Harness Continuity Between Terminals

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   1. Continuity should exist. 
4. Check harness continuity between the following terminals and ground. Refer to WIRING DIAGRAM  .
   Fig 5: Checking Harness Continuity Between Terminals And Ground

   Courtesy of NISSAN MOTOR CO., U.S.A.
   1. Continuity should not exist. 
5. Also check harness for short to power.

OK or NG 

1. OK: GO TO 5.
2. NG: Repair open circuit or short to ground or short to power in harness or connectors.

Perform TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT  .

OK or NG 

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