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Home >> Hyundai >> 2021 >> Tucson Value, FWD >> Repair and Diagnosis (Single Page) >> Engine Performance >> Testing & Diagnosis >> Engine Control System Diagnosis - 2.0L (1 Of 3) >> 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
  • Rationality check
  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
  • Downstream O2 sensor readiness detected
  • Downstream O2 sensor pre-heating phase finished
  • Catalyst temperature (model) is higher than 200°C (392°F).
  • Downstream O2 sensor signal at entry into fuel cut-off is higher than 0.6V.
  • No relevant failure
  • Battery voltage is between 11V and 16V.
Threshold Value
  • Downstream O2S voltage is lower than 800 mV/sec.
Diagnostic Time
  • 3 valid fuel cut-off phases
Mil On Condition
  • 2 Drive Cycles