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Home >> Hyundai >> 2007 >> Entourage GLS >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System Diagnosis (2 Of 2) >> DTC Troubleshooting Procedures >> DTC P0420 Catalyst System Efficiency Below Threshold (Bank 1); DTC P0430 Catalyst System Efficiency Below Threshold (Bank 2) >> Component Inspection
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Component Inspection

  1. Monitor the Catalyst Converter
    1. Clear DTC.
    2. Start the engine and warm it up until the radiator fan comes on ( more than at least 10 minutes).
    3. Drive at a steady speed between 45-55 mph (72-88 km/h) for 30 seconds.
    4. Stop and then maintain idle state for 120 seconds in D-position.
    5. Repeat step  3 once again.
    6. Stop and then keep it in idle state (D-positon) for 120 seconds.
    7. Repeat step  3 once again.
    8. Stop and then maintain idle state for 120 seconds in D-position.
    9. IG "OFF"
    10. Repeat steps  3 through  9 three times.
    11. Check if catalyst monitoring readiness is complete, so, if the readiness is incomplete, repeat steps  2 through  10.
    12. Does the scan tool show DTC P0420?

      YES 

      • Substitute with a known - good Catalyst Converter and check the signal waveform of HO2S for proper operation. If the problem is corrected, Go to "VERIFICATION OF VEHICLE REPAIR " procedure.

      NO 

      • It was intermittent failure.
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