Heated Oxygen Sensor (HO2S) Inspection
HEATED OXYGEN SENSOR TESTINGUsing The Engine Signal Monitor
1. Remove the ECM.
2. Connect the Special Service Tools to the ECM.
3. Warm up the engine to normal operating temperature.
4. Measure the voltage at the ECM terminal 3D, 3H, 31 and 3M.
5. If not as specified, inspect the following.
- Intake-air system
- Fuel system
- On-board diagnosis system
6. If there systems are OK, replace the heated oxygen sensor.
Tightening torque: 30-49 Nm (22-36 ft.lbs.)
Using The New Generation Star Tester
1. Connect the Special Service Tools to the data link connector 2.
2. Select the PID/DATA MONITOR AND RECORD function of NGS.
3. Select "FHO2S R", "RH O2S R", "FHO2S L" and "RHO2S L" on the NGS display. NGS measures and shows the voltage.
4. If not as specified, inspect the following.
- Intake-air system
- Fuel system
- On-Board diagnosis system
5. If these systems are OK, replace the heated oxygen sensor.
Tightening torque: 30-49 Nm (22-36 ft.lbs.)
HEATER
1. Disconnect the heated oxygen sensor connector.
2. Measure the resistance between heated oxygen sensor (front) terminals B and C or between heated oxygen sensor (rear) terminals C and D by using an ohmmeter.
Specification: Approx. 6 ohms 20°C (68°F)
3. If not as specified, replace the heated oxygen sensor.
Tightening torque: 30-49 Nm (22-36 ft.lbs.)