The catalytic converter on bank 1 is not operating efficiently enough to meet emissions standards.
Informational only. Consult a qualified mechanic.
Verify with a scan tool. May need catalytic converter replacement. Check O2 sensors first.
The P0420 OBD-II diagnostic trouble code (DTC) indicates: catalyst system efficiency below threshold bank 1. This is a medium-severity powertrain code that your vehicle's onboard diagnostics system triggers when the catalytic converter on bank 1 is not operating efficiently enough to meet emissions standards. If your check engine light is on with this code, the vehicle is generally safe to drive, but you should have it inspected soon.
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