Procedure For Malfunction A

CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten engine screw on the body.
  Refer to "GROUND INSPECTION ".
  
  Fig 1: Identifying Ground Connections Components
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  OK or NG
  
  OK : GO TO 2.
  
  NG : Repair or replace ground connections.
CHECK HO2S2 GROUND CIRCUIT FOR OPEN AND SHORT
1. Disconnect heated oxygen sensor 2 harness connector (2).
  - <==: Vehicle front
  - Heated oxygen sensor 2 (1)
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 59 and HO2S2 terminal 1. Refer to Wiring Diagram.
  Continuity should exist .
4. Also check harness for short to ground and short to power.
  
  Fig 2: Identifying Heated Oxygen Sensor 2 Harness Connector
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  OK or NG
  
  OK : GO TO 3.
  
  NG : Repair open circuit or short to ground or short to power in harness or connectors.
CHECK HO2S2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal 50 and HO2S2 terminal 4.
  Refer to Wiring Diagram.
  
  Continuity should exist .
2. Check harness continuity between ECM terminal 50 or HO2S2 terminal 4 and ground.
  Refer to Wiring Diagram.
  
  Continuity should not exist .
3. Also check harness for short to power.
  OK or NG
  
  OK : GO TO 4.
  
  NG : Repair open circuit or short to ground or short to power in harness or connectors.
CHECK HO2S2 CONNECTOR FOR WATER
Check connectors for water.

Water should not exist .

OK or NG

OK : GO TO 5.

NG : Repair or replace harness or connectors.
CHECK HEATED OXYGEN SENSOR 2
Refer to "COMPONENT INSPECTION ".

OK or NG

OK : GO TO 6.

NG : Replace heated oxygen sensor 2.
CHECK INTERMITTENT INCIDENT
Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT .

INSPECTION END