Friday, July 31, 2020

2010 Cadillac Truck SRX AWD V6-3.0L Page 936

2010 Cadillac Truck SRX AWD V6-3.0L Page 936



- HO2S Circuit High Voltage Bank 1 Sensor 2



DTC P0151



- HO2S Circuit Low Voltage Bank 2 Sensor 1



DTC P0152



- HO2S Circuit High Voltage Bank 2 Sensor 1



DTC P0157



- HO2S Circuit Low Voltage Bank 2 Sensor 2



DTC P0158



- HO2S Circuit High Voltage Bank 2 Sensor 2



DTC P2A00



- HO2S Circuit Closed Loop Performance Bank 1 Sensor 1



DTC P2A03



- HO2S Circuit Closed Loop Performance Bank 2 Sensor 1



Diagnostic Fault Information



Typical Scan Tool Data



Circuit/System Description



The heated oxygen sensors (HO2S) are used for fuel control and catalyst monitoring. Each HO2S compares the oxygen content of the surrounding



air with the oxygen content of the exhaust stream. When the engine is started, the control module operates in an Open Loop mode, ignoring the



HO2S signal voltage while calculating the air-to-fuel ratio. While the engine runs, the HO2S heats up and begins to generate a voltage within a



range of 0-1,275 mV. Once sufficient HO2S voltage fluctuation is observed by the control module, Closed Loop is entered. The control module



uses the HO2S voltage to determine the air-to-fuel ratio. An HO2S voltage that increases toward 1,000 mV indicates a rich fuel mixture. An HO2S



voltage that decreases toward 0 mV indicates a lean fuel mixture.



The heating elements inside each HO2S heat the sensor to bring the sensor up to operating conditions faster. This allows the system to enter Closed



Loop earlier and the control module to calculate the air-to-fuel ratio sooner.