Main Heated Oxygen Sensor

1. WARM UP ENGINE.
- Allow the engine to warm up to normal operating temperature.





2. INSPECT FEEDBACK VOLTAGE.
- Connect the positive (+) tester probe of a voltmeter to terminal VF1 (for LH bank) or VF2 (for RH bank) of the DLC1, and negative (-) tester probe to terminal E1.





- Perform the test as described above.

HINT: Use SST 09843 - 18020 or equivalent when connecting between terminals TE1 and E1 of the DLC1.





3. DISCONNECT NEGATIVE (-) TERMINAL CABLE FROM BATTERY.

CAUTION: Work must be started after 90 seconds from the time the ignition switch is turned to the 'LOCK' position and the negative (-) terminal cable is disconnected from the battery.





4. INSPECT HEATER RESISTANCE OF MAIN HEATED OXYGEN SENSORS.
- Disconnect the 2 oxygen sensor connectors.
- Using an ohmmeter, measure the resistance between terminals +B and HT.

Resistance: 5.1 - 6.3 Ohms at 20°C (68°F)





- If the resistance is not as specified, replace the sensor.

Torque: 44 Nm (33 ft lb)

- Reconnect the 2 oxygen sensor connectors.
5. RECONNECT NEGATIVE (-) TERMINAL CABLE TO BATTERY.