Toyota 89465-06030 Oxygen Sensor

To check the oxygen sensor, locate the electrical connector and insert pins into the signal and ground terminals, then use a voltmeter to monitor the voltage signal as the engine warms up. The sensor should fluctuate between 0.1 to 0.9 volts in closed-loop mode. Inspect the heater resistance and verify it is receiving battery voltage. If the sensor fails any tests, replace it. To replace the sensor, disconnect the battery, unplug the electrical connector, unscrew the sensor from the exhaust manifold, apply an anti-seize compound to the threads, and install the new sensor. The air/fuel sensor cannot be checked for voltage without a special tool, but the resistance of the heating element can be checked with an ohmmeter. To replace the AF sensor, disconnect the battery, unplug the electrical connector, unscrew the sensor from the exhaust manifold, apply anti-seize compound to the threads, and install the new sensor.