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Heated Oxygen Sensor Heater On-Vehicle 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 specified temperature.

Resistance of HO2S heater
HO2S-1: 5.0 - 6.4 Ohms (at 20 degrees C (68 degrees F)
HO2S-2: 11.7 - 14.3 Ohms (at 20 degrees C (68 degrees F)

3. Connect HO2S coupler securely.