P0420 on the 2008 Honda Fit
The bulletins listed name this code in NHTSA's summary, or are about the same components. A bulletin or a recall listed here may apply to the model year. None of it is a diagnosis.
Nobody has written a description of this code yet.
| SB-10-015 | 2011-04-25. Service bulletin. HONDA: MIL COMES ON WITH DTC P0420 (CATALYST SYSTEM EFFICIENCY BELOW THRESHOLD) IS STORED. ECM/PCM MISINTERPRETS ENGINE IDLE CONDITIONS, RESULTING IN INACCURATE CONTROL OF THE FUEL AND IGNITION. REPLACE CATALYTIC CONVERTER, AND UPDATE THE PGM-FI SOFTWARE WITH HDS. *PE |
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1 on file from NHTSA, as of 2026-10-19. See them in the bulletin list. A bulletin lists model years: read the document for which vehicles it concerns.