DTC P0130, P0136: Ho2S Circuit Malfunction: Notes
NOTE:
There is a Heated Oxygen Sensor (HO2S) before and one after the catalytic converter. The front HO2S measures oxygen content of exhaust gases and is used to control air fuel mixture. The rear HO2S is used to determine the efficiency of the catalytic converter. ECM calculates catalytic converter efficiency by comparing front and rear HO2S signals.