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HOMESERVICE MANUALSHYUNDAI2009TUCSON LIMITED, 2.0 BREPAIR AND DIAGNOSISENGINE PERFORMANCETESTING & DIAGNOSISDTC TROUBLESHOOTING PROCEDURES (2.0L)TROUBLESHOOTING FOR DTCP0420 CATALYST SYSTEM EFFICIENCY BELOW THRESHOLD (BANK 1)DTC DETECTING CONDITION
2009 Hyundai Tucson Limited, 2.0 B

P0420 Catalyst System Efficiency below Threshold (Bank 1): DTC Detecting Condition

2009 Hyundai Tucson Limited, 2.0 BSECTION DTC Detecting Condition
Item Detecting Condition Possible Cause
DTC Strategy
  • Comparison of the signal ratio of upstream and downstream O2 sensor in a load and speed range
  • Exhaust gas leaks
  • Faulty rear HO2S
  • Faulty three way catalyst converter
Enable Conditions
  • Coolant temperature >74°C (165°F)
  • 400°C (752°F) < Catalyst temp, model < 900°C (1652°F)
  • 5km/h (3MPH)< Vehicle speed <180km/h (112MPH)
  • 200 < Mass air flow (mg/rev.) <700
  • Engine speed < 3400 rpm
  • 11V< Battery voltage < 16
  • Lambda regulation active
  • Canister purge valve not in CLOSE state
  • Catalyst purge after fuel cutoff finished
  • No relevant failure
  • 11V< Battery voltage < 16V
Threshold Value
  • Averaged malfunction index > threshold value
Diagnostic Time
  • 100 lambda controller cycles
Mil On Condition
  • 2 Driving Cycles
RENDER: 1.0x

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