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Home >> Kia >> 2019 >> Optima S >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System Diagnosis - 2.4L (2 Of 6) (Except HEV) >> 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
  1. Poor Connector Connection
  2. Air leak in Intake or Exhaust System
  3. Faulty Fuel system
  4. Faulty Downstream O2 Sensor
Enable Condition Case 1
  • Downstream O2 sensor operative readiness detected (sensor element resistance lower than 1kΩ or heater max heating or normal heating for higher than 75s.)
  • O2 sensor internal resistance less than or equal to 3000Ω
  • Catalyst temp. model higher than 752°F (400°C)
  • Downstream O2 sensor signal at entry into fuel cut off higher than 0.6V
  • Battery voltage higher than 11V and lower than 16V
  • No relevant DTC present
Case 2
  • Downstream O2 sensor operative readiness detected (sensor element resistance lower than 1kΩ or heater max heating or normal heating for higher than 75s.)
  • Mass air flow integral after leaving fuel cut off more than 100g
  • Catalyst temp. model higher than 752°F (400°C)
  • Exhaust gas temp. model at sensor location higher than 752°F (400° C)
  • O2 sensor internal resistance less than or equal to 10000Ω
  • Battery voltage higher than 11V and lower than 16V
  • No relevant DTC present
Threshold Value Case 1
  • Average of signal gradient less than 1000mV/s
Case 2
  • Average of signal gradient less than 1500mV/s
Diagnostic Time Case 1
  • 3 valid fuel cut off phases
Case 2
  • 3 valid diagnostic cycles
MIL ON Condition
  • 2 driving cycles