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Home >> Hyundai >> 2012 >> Tucson GL, Automatic Trans >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System Diagnosis (1 Of 3) >> 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 CONDITIONS

Item Detecting Condition Possible Cause
DTC Strategy
  • Slow response (Switching time check at entry in fuel cut off)
  • Leak in intake or exhaust system
  • Faulty fuel system.
  • Front and rear HO2S connections reversed.
  • Poor connection or damaged harness
  • 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 Driving Cycles