P0150

DTC P0150: HO2S Circuit Bank 2 Sensor 1

Wiring Diagram:

Circuit Description
Heated oxygen sensors are used for fuel control and post catalyst monitoring. Each HO2S compares the oxygen content of the surrounding air with the oxygen content of the exhaust stream. When the vehicle is first started, the Engine Control Module (ECM) operates in an Open Loop mode, ignoring the HO2S signal voltage when calculating the air fuel ratio. The ECM supplies the HO2S with a reference voltage of about 0.45 V. The HO2S generates a voltage within a range of 0 - 1 V that fluctuates above and below bias voltage once in Closed Loop. A high HO2S voltage output indicates a rich fuel mixture. A low HO2S voltage output indicates a lean mixture. Heating elements inside the HO2S minimize the time required for the sensors to reach operating temperature, and then provide an accurate voltage signal.

Conditions for Setting the DTC

(Condition 1)
- Ignition ON with the engine running.
- HO2S1 voltage is between 0.376 and 0.474 V.
- Exhaust gas temperature is greater than 349.97 degrees C (661.9 degrees F).
- No oxygen sensor, system voltage faults exist.
- Internal resistance of the oxygen sensor is greater than 60 kOhms. (Condition 2)
- Engine operating state not active.
- Sensor shall be in a state of operative readiness.
- No oxygen sensor fault exists.
- Mass air flow integral during pull cut off phase is greater than 1820.40 g.
- Exhaust gas temperature is 599.9 degrees C (1,112 degrees F) or less.

Action Taken When the DTC Sets
- The Malfunction Indicator Lamp (MIL) will illuminate.
- The ECM will record operating conditions at the time the diagnostic fail. This information will be stored in the Freeze Frame and Failure Records buffers.
- A history DTC is stored.

Conditions for Clearing the MIL/DTC
- The MIL will turn OFF at the end of 3 consecutive validation cycles in which the diagnostic runs without a fault.
- A history DTC will clear after 40 warm up cycles without a fault.
- DTC(s) can be cleared by using the scan tool.

Test Description
The numbers below refer to the step numbers on the diagnostic table.
2. If the voltage is varying above and below the specified value, the condition is not present.

Step 1 - 18:

DTC Troubleshooting