XL-7 Standard 4WD V6-2.7L (2002)
Oxygen Sensor: Testing and Inspection
Heated Oxygen Sensor Heater On-Vehicle Inspection
1. Disconnect HO2S-1 or-2 coupler.
2. Using ohmmeter, measure resistance between terminals "VB" and "GND" of HO2S coupler (1).
If found faulty, replace HO2S.
NOTE: Temperature of HO2S affects resistance value largely. Make sure that HO2S heater is at correct temperature.
3. Connect HO2S coupler securely.