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Home >> Kia >> 2021 >> Niro Plug-In Hybrid LXS >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System Diagnosis (PHEV) (2 Of 6) >> DTC P0139-00: O2 Sensor Circuit Slow Response (Bank 1/Sensor 2) >> DTC Information >> DTC Detecting Condition
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DTC Information: DTC Detecting Condition

Item Detecting Condition Possible Cause
DTC Strategy
  • Response rate monitoring
  • Poor connector connection
  • Air leak in intake or exhaust system
  • Faulty fuel system
  • Faulty downstream O2 sensor
Enable Condition
  • Downstream O2 sensor readiness detected
  • Downstream O2 sensor pre-heating phase finished
  • Catalyst temperature (model) is higher than 200°C (392°F)
  • Downstream O2 sensor signal at entry into fuel cut-off is higher than
  • 0.6V
  • No relevant failure
  • Battery voltage is between 11V and 16V
Threshold Value
  • Downstream O2S voltage is lower than 800mV/s
Diagnostic Time
  • 3 valid fuel cut off phases
MIL ON Condition
  • 2 driving cycles