This code is generic and is the same on all vehicles. P0420 = Catalyst System Efficiency Below ThresholdCatalyst System Efficiency Below Threshold. This means that the secondary O2 sensor detects that the catalytic converter isn't working as efficiently as it should. This engine code can be triggered by any one of the following:
1.) The catalyst in the catalytic converter is cracked, clogged, or otherwise damaged.
2.) The secondary O2 sensor is malfunctioning.
3.) There is an exhaust leak.
4.) The computer unit is faulty
Trouble code P0420 means:Catalyst system efficiency below threshold
Trouble code P0420 means: Catalyst System Efficiency Below Threshold (Bank 1)
P0420 is the catalyst efficiency code. The most common thing is the catalytic converter itself is no longer functioning properly. The other likely thing is the rear oxygen sensor is no longer working properly.
Trouble code P0420 means: Catalyst Efficiency Below Normal (Bank 1)
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P0420 Catalyst System Efficiency Below Threshold (Bank 1)
P0420 : catalyst efficiency failure. You have a failed catalytic converter.
Trouble code P0420 means: Catalyst Efficiency Below Normal (Bank 1)
P0420 Catalyst System Efficiency Below Threshold (Bank 1)
trouble code P0420 means: Catalyst Efficiency Low - A Bank
Trouble code P0420 means: Catalyst Efficiency Below Normal (Bank 1)
Trouble code P0420 means: Catalyst System Efficiency Below Threshold (Bank 1)