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Oxygen Sensor: Testing and Inspection

HEATED OXYGEN SENSOR (Sensor-1 and Sensor-2)




Oxygen Sensor Heater Inspection
1. Disconnect sensor coupler.
2. Using ohmmeter, measure resistance between terminals "V(B)" and "GND" of sensor coupler.

NOTE: Temperature of sensor affects resistance value largely. Make sure that sensor heater is at correct temperature.

Resistance of oxygen sensor heater: 11.7 - 14.3 ohms at 20 °C, 68 °F

If found faulty, replace oxygen sensor.

3. Connect sensor coupler securely.