Diagnostic Procedure

1. Turn ignition switch OFF.
2. Loosen and retighten four 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 

   Fig 3: Checking Voltage Between A/F Sensor 1 Terminal 3 & Ground With CONSULT-II Or Tester

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

OK or NG

• OK: GO TO  4.
• NG: GO TO  3.

Check the following.

• Harness connectors M70, F58
• Fuse block (J/B) connector M4
• 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: A/F Sensor & ECM Terminal Connection Chart (1 Of 2)

   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: A/F Sensor & ECM Terminal Connection Chart (2 Of 2)

   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.