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P0420 OBD Trouble Code

5 results foundP0420 - GenericTypePowertrain - Auxiliary Emission Controls - ISO/SAE ControlledDescriptionCatalyst System Efficiency Below Threshold
LocationBank 1P0420 - ChryslerTypePowertrain - Auxiliary Emission Controls - ISO/SAE ControlledDescriptionCatalyst Efficiency Below Normal Conditions
LocationBank 1CauseEngine running in closed loop for 3 minutes, ECT sensor input over 147°F, engine speed from 1200-1700 rpm with throttle open, VSS over 20 mph, MAP sensor at 1.5-2.0v, then the PCM detected that the switch rate of the rear HO2S-12 reached 70% of the front HO2S-11 switch rate.
P0420 - FordTypePowertrain - Auxiliary Emission Controls - ISO/SAE ControlledDescriptionCatalyst System Efficiency Below Threshold Conditions
CauseEngine running at steady state highway conditions for 5 minutes in closed loop, then the PCM detected that the rear HO2S switch rate was too high
P0420 - GMTypePowertrain - Auxiliary Emission Controls - ISO/SAE ControlledDescriptionCatalyst System Low Efficiency Conditions
LocationBank 1CauseNo PCM codes set, ECT input over 167°F, IAT input over O°F, MAF input 12-32 g/sec, engine speed below 4000 rpm, engine load under 63% and steady for 4 minutes, then engine speed at 1000-3000 rpm and VSS at 30-75 mph and the PCM detected that the catalyst O2 storage capacity was below an acceptable level
P0420 - NissanTypePowertrain - Auxiliary Emission Controls - ISO/SAE ControlledDescriptionCatalytic converter - Bank 1 - efficiency below limit
CauseCatalytic converter, wiring, intake/exhaust system, injector, ECM

 

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P0420 Explained