Oxygen Sensor: Testing and Inspection

ON-VEHICLE INSPECTION
Heated Oxygen Sensor
1. Warm-up the engine to normal operating temperature and run it at idle.

View: Heated Oxygen Sensor Connector:

2. Disconnect the heated oxygen sensor connector.

Heated Oxygen Sensor Terminal Voltage Specifications:

3. Measure the voltage at terminal A.
4. If not as specified, check the intake air system, the fuel system and run the on-board diagnosis test.
5. If these systems are OK, replace the heated oxygen sensor.

Heater Element
1. Disconnect the heated oxygen sensor connector.

Heated Oxygen Sensor Terminal ID:

2. Measure resistance between terminals B and C.

Resistance: Approx. 6 Ohms @ 20°C (68°F)

3. Replace the sensor assembly if not as specified.