Oxygen Sensor Diagnosis

The control module diagnoses the fuel control heated oxygen sensors for the following conditions:

^ Heater Performance (time to activity on cold start)
^ Slow Response
^ Insufficient Switching
^ Transition Time Ratio
^ Inactive Signal (output steady at bias voltage - Approx. 450 mV)
^ Signal Fixed High
^ Signal Fixed Low

The control module diagnoses the three-way catalyst monitor heated oxygen sensors for the following conditions:

^ Heater Performance (time to activity on cold start)
^ Slow response
^ Response Time (time to switch R/L or L/R)
^ Signal fixed Low during steady state conditions or power enrichment (hard acceleration when a rich mixture should be indicated)
^ Signal fixed High during steady state conditions or power enrichment (hard acceleration when a rich mixture should be indicated)
^ Inactive Sensor (output steady at about 438 mv)