When the sensor output is out of specification under enable condition, ECM sets DTC P0137 and turns the MIL on.
Item | Detecting Condition | Possible Cause | |
DTC Strategy |
•
Signal monitoring | 1. Poor connector connection 2. Short to ground in downstream O2 sensor signal circuit 3. Faulty downstream O2 sensor | |
General Enable Condition |
•
30 sec. elapsed after downstream dew point end detected
•
Battery voltage is higher than 11V
•
Exhaust gas temperature around O2 sensor is higher than 350℃(662℉)
•
No downstream O2 sensor heater error | ||
Enable Condition | Case 1 |
•
- | |
Case 2 |
•
Duration of downstream O2 sensor which is signal is below 0.06V after load pulse(End of 3rd pulse) is higher than half duration of previous cycle + 3 sec. | ||
Threshold Value | Case 1 |
•
Downstream O2 sensor voltage is lower than 0.06V | |
Case 2 |
•
Average of voltage difference between loaded and unloaded voltage is lower than 0.015V | ||
Diagnostic Time | Case 1 |
•
20 sec. | |
Case 2 |
•
20 sec. | ||
MIL ON Condition |
•
3 driving cycles | ||
