Diagnostic Procedure

WARNING: This page is about a different car, the 2004 Nissan Murano. However, it is still accessible from the selected car via links, so may be relevant.

RETIGHTEN GROUND SCREWS
1. Turn ignition switch OFF.
2. Loosen and retighten engine ground screws.
1. GO TO 2.
  
  Fig 1: Tightening Engine Ground Screws
  Courtesy of NISSAN MOTOR CO., U.S.A.
CHECK HO2S2 GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect heated oxygen sensor 2 harness connector.
  
  Fig 2: Disconnecting Heated Oxygen Sensor 2 Harness Connectors
  Courtesy of NISSAN MOTOR CO., U.S.A.
3. Check harness continuity between HO2S2 terminal 4 and engine ground. Refer to WIRING DIAGRAM .
  Continuity should exist.
4. Also check harness for short to power.
OK or NG
1. OK: GO TO 4.
2. NG: GO TO 3.
DETECT MALFUNCTIONING PART
Check the following.
- Joint connector-2
- Harness for open or short between HO2S2 and engine ground
1. Repair open circuit or short to power in harness or connectors.
CHECK HO2S2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal and HO2S2 terminal as follows. Refer to WIRING DIAGRAM .
  
  Fig 3: ECM And HO2S2 Terminals Harness Continuity Specifications (P0138, P0158)
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  Continuity should exist.
3. Check harness continuity between the following terminals and ground. Refer to WIRING DIAGRAM .
  
  Fig 4: ECM And HO2S2 Terminals And Ground Harness Continuity Specifications (P0138, P0158)
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  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.
CHECK HO2S2 CONNECTOR FOR WATER
1. Turn ignition switch OFF.
2. Disconnect heated oxygen sensor 2 harness connector.
3. Check connectors for water.
Water should not exist.

OK or NG
1. OK: GO TO 6.
2. NG: Repair or replace harness or connectors.
CHECK HEATED OXYGEN SENSOR 2
Refer to "COMPONENT INSPECTION ".

OK or NG
1. OK: GO TO 7.
2. NG: Replace malfunctioning heated oxygen sensor 2.
CHECK INTERMITTENT INCIDENT
Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".
1. INSPECTION END