General Information

Engine Control
P2243 HO2S Reference Voltage Circuit/Open (Bank 1 / Sensor 1) - 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 PCM monitors this signal and determines whether the air/fuel mixture is rich or lean. The PCM 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 PCM monitors front O2 sensor tip temperature and signal at the same time to check open ciurit of Reference Voltage Circuit ( PCM PIN No. 40). The PCM sets DTC P2243 if front O2 tip temerature is normal during predetermined time and front O2 sensor signal stuck is detected.
If the same error code is set in the next driving cycle, the PCM illuminates the MIL.

DTC Detecting Condition





Schematic Diagram





Signal Waveform