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Home >> Hyundai >> 2005 >> Elantra GLS, 4D Hatchback, Automatic >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Fuel System >> DTC Troubleshooting Procedures >> DTC P0139: Ho2S Circuit Slow Response >> DTC Detecting Condition
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DTC P0139: Ho2S Circuit Slow Response: DTC Detecting Condition

DTC DETECTING CONDITION

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.
  • Contact resistance in connectors
  • HO2S contamination
Enable Condition
  • Coolant temp >74°C(165°F)
  • (VLS_DOWN > 0.68V or < 0.21V) or Catalyst model temp > 500 °C
  • 5km/h(3mph) < Vehicle speed < 180km/h(112mph)
  • Sensor preheating and full phase finished
  • Catalyst temp. model >350°C(662°F)
  • No relevant failure
  • 11V < Battery voltage < 16V
  • Downstream O2 sensor signal at entry in fuel cut off > 0.55V
Threshold Value
  • Average ratio(between measured and maximum allowed switching time at entry in fuel cut-off) > 1
Diagnostic Time
  • 5 fuel cut-off phases