Introduction to On Board Diagnostics (II)

Fundamentals of PowertrainControl strategies & OBD IIDiagnosticsOxygen Sensor (O 2 ) Sensor ( DTCs 130-167):167): O 2sensor diagnostics areperformed to check deterioration of electrochemical pumping action thatgenerates voltage sensitivity to the oxygen density in the exhaustmanifold. In case of Zirconia electrode circuit malfunction fault code 130is assigned. If the O 2sensor is indicating slow response fault code 133 isassigned. The expected value is estimated using closed-loop loop frequencyand engine parameters. If the O 2sensor is indicating very low voltagefault code 131 is assigned. If the O 2sensor is indicating very highvoltage fault code 132 is assigned. If the O 2sensor is indicating noactivity, fault code 134 is assigned. In case of O 2sensor heater circuitmalfunction fault code 135 is assigned. The other codes from 135 5 to 167are assigned to similar faults for other O 2sensors and heaters in othercatalytic converters in the system. Oxygen sensor diagnostics are adescribed in detail in alter section.