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Home >> Toyota >> 2002 >> Highlander 2WD L4-2.4L (2AZ-FE) >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Oxygen Sensor >> Testing and Inspection
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Oxygen Sensor: Testing and Inspection





INSPECT HEATER RESISTANCE OF A/F SENSOR (No. 1, No. 4 Cylinder side)
a. Disconnect the A/F sensor connector.

b. Using an ohmmeter, measure the resistance between the terminals +B and HT.
Resistance:
1.8 - 3.4 (Ohm) at 20 °C (68 °F)
5.0 - 7.5 (Ohm) at 500 °C (932 °F)
If the resistance is not as specified, replace the sensor.

c. Reconnect the A/F sensor connector.





INSPECT HEATER RESISTANCE OF A/F SENSOR (No. 2, No. 3 Cylinder side)
a. Disconnect the A/F sensor connector.

b. Using an ohmmeter, measure the resistance between the terminals +B and HT.
Resistance:
1.8 - 3.4 (Ohm) at 20 °C (68 °F)
5.0 - 7.5 (Ohm) at 500 °C (932 °F)
It the resistance is not as specified, replace the sensor.

c. Reconnect the A/F sensor connector.





INSPECT HEATER RESISTANCE OF OXYGEN SENSORS
a. Disconnect the oxygen sensor connector.

b. Using an ohmmeter, measure the resistance between the terminals +B and HT.
Resistance: 11 - 16 (Ohm) at 20°C (68°F)
If the resistance is not as specified, replace the sensor.

c. Reconnect the oxygen sensor connector.
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