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CIRCUIT DESCRIPTION This diagnostic applies only to vehicles built with Delphi heated oxygen sensors. To identify the heated oxygen sensor refer to Delphi/Denso Sensor in Computers and Control Systems Component Views.The Powertrain Control Module (PCM) monitors the Heated Oxygen Sensor (HO2S) activity for 100 seconds . During this monitor period the PCM counts the number of times that the HO2S switches from rich to lean and lean to rich. A DTC P1133 or P1153 sets when the PCM determines that the HO2S did not switch enough times.A lean to rich switch is determined when the HO2S voltage changes from less than 300 mV to more than 600 mV . A rich to lean switch is determined when the HO2S voltage changes from more than 600 mV to less than 300 mV .CONDITIONS FOR RUNNING THE DTC
CONDITIONS FOR SETTING THE DTC The HO2S lean-to-rich and rich-to-lean switches are less than a calibrated value for 100 seconds .ACTION TAKEN WHEN THE DTC SETS
CONDITIONS FOR CLEARING THE MIL/DTC
DIAGNOSTIC AIDS IMPORTANT: Remove any debris from the PCM connector surfaces before servicing the PCM. Inspect the PCM connector gaskets when diagnosing/replacing the PCM. Ensure that the gaskets are installed correctly. The gaskets prevent water intrusion into the PCM.
For an intermittent, Refer to Intermittent Conditions. See: Symptom Related Diagnostic Procedures\Intermittent ConditionsTEST DESCRIPTION