Oxygen Sensor Monitor

OBD System Description - Oxygen Sensor Monitor

System Description / Monitoring Procedure

Primary HO2S
For a primary HO2S, the system monitors maximum and minimum voltage, lean-to-rich and rich-to-lean response rates, and switching cycles during monitoring conditions continuous. The sensor is also monitored for activity continuously.

Secondary HO2S
A secondary HO2S is used for catalyst monitoring. With non-aged catalyst system, amplitude of the voltage changing is very narrow and slow. But along with aging of the catalyst, the amplitude is going to be wider and quicker. Then the system calculates average of the voltage during monitoring conditions once per driving cycle, and compares the average with malfunction criteria.

DTC Description / Detecting Condition / Confirmation Procedure

P0131
Refer to DTC P0131: HO2S (Bank-1 Sensor-1) Circuit Low Voltage:H25 Engine.

P0132
Refer to DTC P0132: HO2S (Bank-1 Sensor-1) Circuit High Voltage:H25 Engine.

P0133
Refer to DTC P0133: HO2S (Bank-1 Sensor-1) Circuit Slow Response:H25 Engine.

P0134
Refer to DTC P0134: HO2S (Bank-1 Sensor-1) No Activity Detected:H25 Engine.

P0137, P0138
Refer to DTC P0137 / P0138: HO2S (Bank-1 Sensor-2) Circuit Low / High Voltage:H25 Engine.

P0151
Refer to DTC P0151: HO2S (Bank-2 Sensor-1) Circuit Low Voltage:H25 Engine.

P0152
Refer to DTC P0152: HO2S (Bank-2 Sensor-1) Circuit High Voltage:H25 Engine.

P0153
Refer to DTC P0153: HO2S (Bank-2 Sensor-1) Circuit Slow Response:H25 Engine.

P0154
Refer to DTC P0154: HO2S (Bank-2 Sensor-1) No Activity Detected:H25 Engine.

P0157, P0158
Refer to DTC P0157, P0158: HO2S (Bank-2 Sensor-2) Circuit Low/High Voltage:H25 Engine.