Oxygen Sensor: Testing and Inspection

HEATED OXYGEN SENSOR -1 and -2 (HO2S-1 AND HO2S-2)

Oxygen Sensor - 1 Inspection
Inspect oxygen sensor and its circuit referring to DTC P0131/P0132 Diag. Flow Table in "Computers/Testing/Trouble Code Procedures". If malfunction is found, replace.




Oxygen Sensor Heater Inspection (Sensor - 1 and - 2)
1. Disconnect oxygen sensor coupler.
2. Using ohmmeter, measure resistance between terminals "Ve" 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) for HO2S-1 without WU-TWC and sensor - 2

4.5 - 5.7 Ohms. (at 20 °C, 68 °F) for HO2S-1 with WU-TWC

If found faulty, replace oxygen sensor.

3. Connect oxygen sensor coupler securely.