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Home >> Hyundai >> 2009 >> Elantra Touring Standard >> Repair and Diagnosis >> Engine Performance >> System >> DTC Troubleshooting Procedures >> Inspection Chart For Diagnostic Trouble Codes (DTC) >> P0139 O2 Sensor Circuit Slow Response (Bank 1/Sensor 2) >> DTC Detecting Condition
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P0139 O2 Sensor Circuit Slow Response (Bank 1/Sensor 2): DTC Detecting Condition

P0139 O2 SENSOR CIRCUIT SLOW RESPONSE (BANK 1/SENSOR 2)

Item Detecting Condition Possible Cause
DTC Strategy
  • 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
  • Catalyst temp.model >350°C (662°F)
  • No relevant failure
  • 11V < Battery voltage
  • Downstream O2 sensor signal at entry in fuel cut off > 0.55V
  • 4.8Km/h (3MPH)<Vehicle speed<180Km/h (112MPH)
Threshold Value
  • Average ratio (between measured and maximum allowed switching time at entry in fuel cutoff) > 1
Diagnostic Time
  • 3 fuel cutoff phases
Mil On Condition
  • 2 Driving Cycles