Oxygen Sensor: Testing and Inspection

CIRCUIT DIAGRAM





USING SCAN TOOL








HARNESS INSPECTION PROCEDURES

SENSOR INSPECTION

1. Warm up the engine and check that engine coolant temperature is 80-90°C (176-194°F).





2. Disconnect the oxygen sensor and connect the digital Voltmeter.

Caution: Do not pull the connector and lead wires strongly when disconnecting the oxygen sensor connector.

3. While repeatedly racing the engine, measure the output Voltage of the oxygen sensor.





4. Replace the oxygen sensor if it is faulty.

TROUBLESHOOTING HINTS
An oxygen sensor problem does not usually affect the driveability. More noticible is an increase in hazzardous emissions (HC, CO, NOx) in the exhaust gas control system is not in closed loop mode.