This Direct Trouble Code (DTC) is set when, through normal wear and tear, your vehicle's catalytic converter has exceeded it's useful life expectancy. Basically, your catalytic converter is used up and you need a new one. In the diagrams down below I have included a factory diagnostic troubleshooting guide for your vehicle for DTC P0420. Please go through it and get back to us with what you are able to find out.
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Thursday, August 15th, 2019 AT 6:09 PM