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Home >> Hyundai >> 2021 >> Elantra Limited >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System Diagnosis - 2.0L (Except HEV) (2 Of 6) >> DTC P0140-00: O2 Sensor Circuit No Activity Detected (Bank 1/Sensor 2) >> DTC Information And Inspection >> DTC Detecting Condition
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DTC Information And Inspection: DTC Detecting Condition

Item Detecting Condition Possible Cause
DTC Strategy Case 1
  • Signal plausibility with rich mixture (during catalyst purge after fuel cut-off)
  1. Poor connector connection
  2. Faulty downstream O2 sensor circuit
  3. Faulty downstream O2 sensor
Case 2
  • Signal rationality with lean mixture (during fuel cut-off)
Enable Condition Case 1
  • ECTS is more than 73°C (163°F)
  • Downstream HO2S operative readiness detected
  • Downstream HO2S pre-heating phase finished
  • Integrated MAFS in last fuel cut-off is more than 4g
  • Downstream HO2S signal at end of last fuel cut off is less than 0.3V
  • Integrated air MAFS in Part Load is more than 150g
  • Minimum upstream HO2S voltage during catalyst purge phase is more than 0.6V
  • Modeled catalyst temperature is more than 400°C (752° F)
  • No relevant failure
  • Battery voltage between 11 and 16V
Case 2
  • Downstream HO2S operative readiness detected
  • Downstream HO2S pre-heating phase finished
  • Integrated MAFS since fuel cut-off begin between 12 and 250g
  • No relevant failure
  • Battery voltage between 10 and 16V
Threshold Value Case 1
  • Max. downstream HO2S is less than 0.6V during catalyst purge after fuel cut-off
Case 2
  • Downstream HO2S is more than 0.3V during fuel cut-off phase
Diagnostic Time Case 1
  • 3 valid fuel cut-off followed by catalyst enrichment phases
Case 2
  • 5s
MIL ON Condition
  • 2 driving cycles