P1420 on the 2003 Honda Civic
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.
This code is specific to a manufacturer and is not described here. Its meaning is in the manufacturer's service information.
| 1204 | 2005-12-15. Service bulletin. DIAGNOSTIC TROUBLE CODE P0420 AND P1420 REPAIRS. *TT |
|---|---|
| 04032 | 2004-12-10. Service bulletin. MALFUNCTION INDICATOR LAMP COMES ON WITH DIAGNOSTIC TROUBLE CODE P1420. *TT |
2 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.