# code 0420



## ifix777 (Apr 26, 2007)

i own a 2000 Maxima with the ses light on for code 0420. I troubleshot per the nissan repair manual, and i narrow it down to the last 2 possible causes, re-programing of the ecm, or a malfunction of the 3 way catalyst. Assuming the re-programing does not fix, does anyone have any experience on replacing the 3 way catalyst, or any tips on where to purchase one? thanks


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## mpe235 (Jan 19, 2009)

You can purchase it at a dealer or an aftermarket supplier. The aftermarket ones look a little different but they do work.


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