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Home >> Kia >> 2013 >> Optima SX >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System Diagnosis (1 Of 3) - 2.0L >> DTC P0139: O2 Sensor Circuit Slow Response (Bank 1/Sensor 2) >> General Information >> DTC Detecting Condition
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General Information: DTC Detecting Condition

DTC DETECTING CONDITION AND POSSIBLE CAUSES

Item Detecting Condition Possible Cause
DTC Strategy
  • Slow response (Switching time check at entry in fuel cut off)
  1. Leak in intake or exhaust system
  2. Faulty fuel system.
  3. Front and rear HO2S connections reversed.
  4. Poor connection or damaged harness
  5. HO2S contamination
Enable Conditions
  • Coolant temperature >73°C (163°F)
  • Downstream O2 sensor readiness detected
  • Downstream O2 sensor pre-heating phase finished
  • 400°C (752°F) < Catalyst temperature model
  • 0.6V < Downstream O2 sensor signal at entry into fuel cut-off
  • No relevant failure
  • 11V < Battery voltage < 16V
Threshold Value
  • Average ratio between measured and maximum allowed rich to lean switching time entering fuel cut-off >1
Diagnostic Time
  • 4 valid fuel cut-off phases
Mil On Condition
  • 2 Drive Cycles