A heated oxygen sensor (HO2S) indicating rich at the end of a test is trying to correct for an over lean condition. This DTC sets when the fuel control system no longer detects switching for a calibrated amount of time.
Item | Detecting Condition | Possible Cause |
DTC Strategy |
•
Check Signal Stuck Rich | 1. Poor connection 2. S1 3. Blocking of intake system 4. Fuel leakage in injector 5. Improper fuel pressure |
Enable Conditions |
•
350 ℃(662 °F) < Exhaust Gas Temp < 800 ℃(1472 °F)
•
Required Lambda = 1
•
Integrated exhaust gas mass after above condition > 35 g | |
Threshold Value |
•
Secondary control variable by downstream O2 sensor < -0.07 | |
Diagnostic Time |
•
40 sec. | |
MIL ON Condition |
•
2 Driving Cycles |
※ S1 : upstream oxygen sensor / S2 : downstream oxygen sensor