General Information

Component Location





General Description

The linear O2 sensor is mounted on the front side of the Catalytic Converter (warm-up catalytic converter) or in the front exhaust pipe. It detects a wide range of air/fuel ratios in the exhaust gas from the rich to lean regions. This linear O2 sensor produces a current that corresponds to a specific air/fuel ratio. The ECM monitors this signal and determines whether the air/fuel mixture is rich or lean. The ECM constantly monitors the linear O2 sensor and increases or decreases the fuel injection duration using this signal. This is called closed-loop fuel control operation.

DTC Description

The ECM monitors front HO2S tip temperature and signal at the same time to check open circuit of Pumping Current Circuit (ECM PIN No. 44). The ECM sets DTC P2237 if front O2 tip temperature is higher than the predetermined threshold and front HO2S signal stuck is detected.
If the same error code is set in the next driving cycle, the ECM illuminates the MIL.

DTC Detecting Condition





Schematic Diagram





Signal Waveform