Diagnostic Procedure

1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.

   Refer to "GROUND INSPECTION ".

   Fig 1: Checking Ground Connections

   Courtesy of NISSAN MOTOR CO., U.S.A.

OK or NG

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

1. Disconnect air fuel ratio (A/F) sensor 1 harness connector.
   Fig 2: Disconnecting Air Fuel Ratio (A/F) Sensor 1 Harness Connector

   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.

   Voltage: Battery voltage 

OK or NG

• OK: GO TO  4.
• NG: GO TO 3.

Fig 3: Checking Voltage Between A/F Sensor 1 Terminal 3 And Ground

Courtesy of NISSAN MOTOR CO., U.S.A.

Check the following.

• Harness connectors E21, F34
• IPDM E/R harness connector E122
• 15A fuse
• Harness for open or short between A/F sensor 1 and fuse
  • : 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: Terminals Chart For Checking Continuity

   Courtesy of NISSAN MOTOR CO., U.S.A.

   Continuity should exist. 

4. Check harness continuity between the following terminals and ground.

   Refer to WIRING DIAGRAM .

   Fig 5: Terminals Chart For Checking Continuity To Ground

   Courtesy of NISSAN MOTOR CO., U.S.A.

   Continuity should not exist. 

5. Also check harness for short to power.

OK or NG

• OK: GO TO 5.
• 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

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