General Information

Component Location





General Description

The heated oxygen sensors are mounted on the front side and the rear side of Catalytic Converter (warm-up catalytic converter), which detects the oxygen concentration in the exhaust gas. The front HO2S signal is used to control air/fuel ratio (closed loop fuel control) and the rear HO2S signal is used to monitor front HO2S and catalyst for proper operation. The heated oxygen sensor (HO2S) produces a voltage that varies between 0 V and 1 V. When the air/fuel ratio is lean, the oxygen concentration in the exhaust gas increases and the front HO2S outputs a low voltage (approximately 0 - 0.4 V).
When the air/fuel ratio is rich, the oxygen concentration in the exhaust gas decreases and the front HO2S outputs a high voltage (approximately 0.6 - 1 V). The ECM constantly monitors the HO2S and increases or decreases the fuel injection duration by using the HO2S signal, which is called closed-loop fuel control operation.

DTC Description

If the sensor output is over 1.08 V under enable conditions, ECM sets P0132.
(This DTC might be caused by the malfunction of Heater circuit, so, check the heater circuit first.)

DTC Detecting Condition





** B1S1 : upstream oxygen sensor / B1S2 : downstream oxygen sensor

Specification





Schematic Diagram





Signal Waveform