Air-Fuel Ratio (A/F) Sensor

INSPECT HEATER RESISTANCE OF A/F SENSORS
a. Disconnect the A/F sensor connector.
b. Using an ohmmeter, measure the resistance between the terminals +B and HT.

Resistance:
0.8 - 1.4 ohms at 20 °C (68 °F)
1.8 - 3.2 ohms at 800 °C (1,472 °F)

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

c. Reconnect the A/F sensor connector.