If the sensor output is below 0.06 V and the average of voltage difference between loaded and unloaded voltage is below 0.015 V under enable conditions, the PCM sets DTC P0137.
Item | Detecting Condition | Possible Cause | |
Case 1 | DTC Strategy |
•
Signal check, low by Load pulse. | 1. Poor connection 2. Short to ground in signal circuit 3. HO2S(S2) |
Enable Conditions |
•
Duration of down O2S less than 0.06V for more than 3 sec.
•
Load pulse : End of 3rd pulse. | ||
Threshold Value |
•
Average of voltage difference between loaded and unloaded voltage less than 0.015 V. | ||
Diagnostic Time |
•
3 sec. | ||
Case 2 | DTC Strategy |
•
Signal check, low. | |
Enable Conditions |
•
Short term FT less than 1.25 (upper limit).
•
B+ greater than 10.7 V.
•
Heat quantity from exhaust gas.
•
Around downstream O2S greater than 1~312 kJ. | ||
Threshold Value |
•
Downstream O2S voltage less than 0.06 V. | ||
Diagnostic Time |
•
40 sec. | ||
MIL ON Condition |
•
2 driving cycles. | ||
※ S2 : upstream oxygen sensor / S2 : downstream oxygen sensor
