If the sensor output signal is over 1.08 V under enable conditions, the ECM sets DTC P0138.
Item | Detecting Condition | Possible Cause |
DTC Strategy |
•
Signal check, high | 1. Poor connection 2. Short to power in signal circuit 3. S2 |
Enable Conditions |
•
Battery voltage > 10.7 V
•
Heat quantity from exhaust gas around downstream O2S > 1~312 kJ | |
Threshold Value |
•
S2 sensor voltage > 1.08 V | |
Diagnostic Time |
•
2.5 sec. | |
MIL ON Condition |
•
2 driving cycles |
※ S1 : upstream oxygen sensor / S2 : downstream oxygen sensor