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HOMESERVICE MANUALSHYUNDAI2009SONATA SE, 3.3 FREPAIR AND DIAGNOSIS (SINGLE PAGE)ENGINE PERFORMANCETESTING & DIAGNOSISDTC TROUBLESHOOTING PROCEDURES - 3.3L (2 OF 2)TROUBLESHOOTING FOR DTCDTC P0420: CATALYST SYSTEM EFFICIENCY BELOW THRESHOLD (BANK 1)DTC DETECTING CONDITION
2009 Hyundai Sonata SE, 3.3 F

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

2009 Hyundai Sonata SE, 3.3 FSECTION DTC Detecting Condition
DTC DETECTING CONDITION CHART

Item Detecting Condition Possible cause
DTC Strategy
  • Manipulates Airfuel and stores the times it takes for the pre and post converter oxygen sensors to switch.
  • Catalyst Converter
Enable Condition
  • Engine Runtime ≥ 580 sec.
  • Purge Concentration Learned
  • 3 g/s ≤ Airflow ≤ 10g/s
  • Throttle closed ≤ 1.5%
  • 70°C (158°F) ≤ Coolant Temp. ≤ 120°C (248°F)
  • -7°C (19.4°F) ≤ Ambient Temp. ≤ 105°C (221°F)
  • Barometer ≥ 72 kPa
  • Max number of test attempts ≤ 12
  • Closed Loop
  • 250°C (482°F) ≤ Catalyst Temp. ≤ 950°C (1742°F)
  • Fuel learning completed
  • Vehicle speed ≤ 3 kph (1.8 mph)
  • Not airfuel ramping
  • Max idle time (about 60 sec.) not exceeded
  • No disabling faults present
  • No instrumentation slews active
Threshold value
  • Oxygen Storage Time < 3.25 sec.
Diagnosis time
  • 15 sec.
MIL ON Condition
  • 1 Driving cycle
RENDER: 1.0x

NO RELATED

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