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.
If the HO2S signal voltage is fixed at lean status, then feedback control is no longer possible, the PCM sets DTC P2195.
Item | Detecting Condition | Possible cause |
DTC Strategy |
•
Characteristic line strong shift | 1. Poor connection or damaged harness 2. Front HO2S |
Enable Conditions |
•
Wide range sensor pump current valid
•
Downstream O2 sensor operative readiness
•
Active test not activated
•
ngine speed ＞ 600rpm
•
Mass air flow ＜ 83g/sec(300kg/h)
•
572 F(300℃) ＜ Exhaust gas temperature ＜ 1472 F (800℃) | |
Threshold value |
•
Plausibility between upstream and downstream
•
Upstream lean & downstream rich & lambda controller limit or upstream rich & downstrean lean & lambda controller limit | |
Diagnosis Time |
•
Less than 1300 sec. | |
MIL On Condition |
•
2 driving cycle |
