ECM shows P2237 when the conditions are like below.
- Deviation of average correction value of fuel ratio is higher than 0.1 when sensor voltage is 1.49~1.5V
- Accumulated air mass flow value is higher than threshold value when target lambda is 0.97
- Upstream O2 sensor displays 1.7V below when the fuel cut is being kept over 3 minutes.
Item | Detecting Condition | Possible Cause | |
DTC Strategy |
•
Rationality check | 1. Poor connection 2. Open or short power/ground in signal circuit 3. S1 | |
Case1 | Enable Conditions |
•
S1 sensor voltage is higher than 1.49V and lower than 1.5V | |
ThresholdValue |
•
Deviation of average correction value of fuel ratio is higher than 0.1 | ||
DiagnosticTime |
•
3 sec | ||
Case2 | Enable Conditions |
•
Fuel cut condition is higher than 3sec | |
ThresholdValue |
•
S1 sensor voltage is lower than 1.7V | ||
DiagnosticTime |
•
5 sec | ||
Case3 | Enable Conditions |
•
Target value of fuel ratio is lower than 0.97
•
S1 sensor voltage is higher than 1.49V and lower than 1.5V | |
ThresholdValue |
•
Integrated air mass is higher than 0.2㎏ | ||
ThresholdValue |
•
3 sec | ||
MIL ON Condition |
•
2 driving cycle | ||
