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

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

1. Disconnect A/F sensor 1 harness connector.
2. Turn ignition switch ON.
   Fig 2: Disconnecting A/F Sensor 1 Harness Connector

   Courtesy of NISSAN MOTOR CO., U.S.A.
3. Check voltage between A/F sensor 1 terminal 3 and ground with CONSULT-II or tester.

   Voltage: Battery voltage 

OK or NG

1. OK : GO TO  4.
2. 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 E21, F34
• IPDM E/R harness connector E122
• 10A fuse
• Harness for open or short between A/F sensor 1 and fuse

1. : Repair or replace harness or connectors.

1. Disconnect ECM harness connector.
2. Check harness continuity between the following terminals. Refer to Wiring Diagram .
   HARNESS CONTINUITY TERMINALS REFERENCE
   
   

   A/F sensor 1 terminal	ECM terminal
   1	16
   5	35
   6	56
   2	75

   Continuity should exist. 

3. Check harness continuity between ECM terminals 16, 35, 56, 75 or A/F sensor 1 terminals 1, 2, 5, 6 and ground. Refer to Wiring Diagram .

   Continuity should not exist. 

4. 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.