Oxygen Sensor: Testing and Inspection

Inspection of Terminal Voltage

1. Warm up the engine and run it at idle.

2. Disconnect the oxygen sensor connector.

3. Connect a voltmeter between the oxygen sensor and a ground.

4. Run the engine at 4,500 rpm until the voltmeter indicates approx. O.7V.






5. Increase and decrease the engine speed suddenly sever a times. Check to see that when the speed is increased the meter reads between O.5V-1.OV and when the speed is decreased it reads between OV-O.4V.

6. If not as specified, replace the oxygen sensor.







Inspection of Sensitivity

1. Warm up the engine to the normal operating temperature.

2. Connect the SST to the check connector (Green: 6-pin) and the negative battery terminal.


Note

Do not ground the test connector (Green: 1-pin) during inspecting the oxygen sensor sensitivity.







3. Increase the engine speed to between 2,000 and 3,000 rpm, and check that the monitor lamp flashes for 10 seconds.


Monitor lamp: Flashes more than 8 times/10 seconds







Replacement

1. Disconnect the oxygen sensor connector.

2. Remove the oxygen sensor.

3. Install and tighten the oxygen sensor to specified torque.


Tightening torque:

29-49 Nm (3-5 m-kg, 22-36 ft-lb)


4. Connect the oxygen sensor connector.