If amplitude of S2 is different from the model value during 60 sec under enable conditions, ECM sets DTC P0420.
Item | Detecting Condition | Possible Cause |
DTC Strategy |
•
Oxygen storage capacity (Deterioration ofCatalytic efficieny) | 1. Exhaust system 2. S2 3. Catalystconverter |
Enable Conditions |
•
Engine speed 1720∼2800rpm
•
Engine load 21 ∼63 %
•
Catalyst temp.(model) > 500℃
•
Closed loop control
•
There is not misfire.
•
There is not malfunction on HO2S / PCSV / ECTS. | |
Threshold Value |
•
Difference of ‘amplitude of downstream O2 sensor’ and ‘amplitude of model signal’ > 0.7 | |
Diagnostic Time |
•
100 sec | |
MIL ON Condition |
•
3 driving cycle |
※ S1 : upstream oxygen sensor / S2 : downstream oxygen sensor
