Fault Criteria, Rear Heated Oxygen Sensor

The oxygen sensor's activity is diagnosed once per trip.
When the conditions for diagnosis are fulfilled, the sensor's change in voltage and voltage level are measured.
If sensor voltage does not change by a sufficient amount and does not exceed a certain level within a certain time, the sensor is defective.
If sensor voltage does not change by more than 0.5 V and does not exceed 0.4 V in 500 seconds, the fault criteria are satisfied.
In other respects the sensor and its preheater are monitored according to the On-Board Diagnostic I model for the front heated oxygen sensor.

Conditions For Diagnosis
^ Diagnosis not yet performed this trip
^ Engine running
^ Vehicle speed above 0 km/h
^ Coolant temperature above 70 °C (158 °F)
^ Sensor preheater activated