Diagnostic Procedure

1. Turn ignition switch OFF.
2. Loosen and retighten ground three screws on the body.
   Fig 1: DTC P1276, P1286 Checking Ground Connections

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

   Refer to GROUND INSPECTION .

OK or NG

OK: GO TO 2.

NG: Repair or replace ground connections.

1. Disconnect A/F sensor 1 harness connector.
   Fig 2: Locating A/F Sensor 1 Harness Connectors

   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 & Ground

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

Check the following.

• Harness connectors E5, F14
• IPDM E/R harness connector E119
• 10A 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 A/F sensor 1 terminal and ECM terminal as follows. Refer to Wiring Diagram.
   Fig 4: Checking A/F Sensor 1 Input Signal Circuit Continuity Reference Table (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: Checking A/F Sensor 1 Input Signal Circuit Continuity Reference Table (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.