Oxygen Sensor: Testing and Inspection

Out of Range Voltage

The following Diagnostic Trouble Codes (DTCs) indicate that the ECM has detected an HO2S signal voltage that is outside of the normal operating range of the sensor:

^ DTC P0130 - HO2S Circuit - Bank 1 Sensor 1 P0130

^ DTC P0136 - HO2S Circuit - Bank 2 Sensor 1 P0136

^ DTC P0150 - HO2S Circuit - Bank 1 Sensor 2 P0150

^ DTC P0156 - HO2S Circuit - Bank 2 Sensor 2 P0156

Low Voltage

The following DTCs indicate that the ECM has detected an HO2S signal voltage that remains excessively low:

^ DTC P0131 - HO2S Circuit Low Voltage - Bank 1 Sensor 1 P0131

^ DTC P0137 - HO2S Circuit Low Voltage - Bank 2 Sensor 1 P0137

^ DTC P0151 - HO2S Circuit Low Voltage - Bank 1 Sensor 2 P0151

^ DTC P0157 - HO2S Circuit Low Voltage - Bank 2 Sensor 2 P0157

High Voltage

The following DTCs indicate that the ECM has detected an HO2S signal voltage that remains excessively high:

^ DTC P0132 - HO2S Circuit High Voltage - Bank 1 Sensor 1 P0132

^ DTC P0138 - HO2S Circuit High Voltage - Bank 2 Sensor 1 P0138

^ DTC P0152 - HO2S Circuit High Voltage - Bank 1 Sensor 2 P0152

^ DTC P0158 - HO2S Circuit High Voltage - Bank 2 Sensor 2 P0158

Igntion Feed or Ground Problem

A fault in the heated oxygen sensor heater element or the related ignition feed or ground will result in an increase in time to a Closed Loop fuel control. This may cause increased emissions, especially at start-up. The following DTCs indicate that the ECM detects a problem with an HO2S Heater:

^ DTC P0135 - HO2S Heater Circuit - Bank 1 Sensor 1 P0135

^ DTC P0141 - HO2S Heater Circuit - Bank 2 Sensor 1 P0141

^ DTC P0155 - HO2S Heater Circuit - Bank 1 Sensor 2 P0155

^ DTC P0161 - HO2S Heater Circuit - Bank 2 Sensor 2 P0161

HO2S Response Time

The ECM also has the ability to evaluate HO2S response time and whether or not there is sufficient signal activity. If a problem is detected, the ECM will store a DTC indicating degraded HO2S performance.