Diagnostic Procedure
- Check Ground Connections
- Turn ignition switch OFF.
- Loosen and retighten three ground screws on the body. See Figure
.
Refer to GROUND INSPECTION .
OK or NG
- OK: go to 2 .
- NG: Repair or replace ground connections.
- Retighten Heated Oxygen Sensor 1
- Check HO2S1 Ground Circuit For Open And Short
- Disconnect heated oxygen sensor 1 harness connector.
- Disconnect ECM harness connector.
- Check harness continuity between HO2S1 terminal 4 and ECM terminal 78.
Refer to wiring diagram. See Figure or Figure .
- Continuity should exist .
- Also check harness for short to ground and 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 HO2S1 Input Signal Circuit For Open And Short
- Check harness continuity between ECM terminal and HO2S1 terminal as follows.
Refer to wiring diagram. See Figure or Figure .
Courtesy of NISSAN MOTOR CO., U.S.A.
- Continuity should exist .
- Check harness continuity between the following terminals and ground.
Refer to wiring diagram. See Figure or Figure .
For testing procedures, see Fig 2 .
- Continuity should not exist .
- Also check harness for short to ground and 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.
- Check harness continuity between ECM terminal and HO2S1 terminal as follows.
- Check HO2S1 Connector For Water
- Turn ignition switch OFF.
- Disconnect heated oxygen sensor 1 harness connector.
- Check connectors for water.
- Water should not exist .
OK or NG
- OK: go to 6 .
- NG: Repair or replace harness or connectors.
- Check Heated Oxygen Sensor 1
Refer to COMPONENT INSPECTION .
OK or NG
- OK: go to 7 .
- NG: Replace malfunctioning heated oxygen sensor 1.
- Check Intermittent Incident
Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT .
- Inspection end