If the lambda controller reaches the maximum or minimum threshold, then feedback control is no longer possible and emissions will be increased. The ECM sets DTC P2097 if no proportional post catalyst fuel trim adaptation occurs for a defined time after the lambda controller has reached its minimum threshold.
Item | Detecting Condition | Possible Cause |
DTC Strategy |
•
O2 sensor characteristic shift rate monitoring | 1. Poor connector connection 2. Air leak in exhaust system 3. Faulty Three-way Catalytic Converter |
Enable Condition |
•
30 sec. elapsed after upstream dew point end detected
•
Fuel feedback control active
•
Battery voltage is higher than 11V
•
Exhaust gas temperature is at between 400℃(752℉) and 800℃(1472℉)
•
No injector error
•
No upstream O2 sensor heater error | |
Enable Condition |
•
No catalyst error detected
•
No misfire occurred | |
Threshold Value |
•
I-portion of lambda controller value by downstream O2 sensor is less than -0.03 | |
Diagnosis Time |
•
20 sec. | |
MIL ON Condition |
•
3 driving cycles |
