05' Pathfinder throws p0430

My parents have an 05' Pathfinder I'm trying to diagnose, and it throws P0430(Bank 2 Cat below threshold) Doesn't have any drivability issues. STFT & LTFT from freeze frame all show within -+10%. so, no problem there. Does anyone know if the Pathfinder is famous for this code? Where should I start? I already cleared the code to verify the concern and it came back on after a few days. Should I go ahead and try a PCM relearn. Any info is greatly appreciated.

I think your cat is done. The ecm monitors the cross counts switching of the front and rear o2 sensors. When they are switching at the near the same rate this codes sets. At nissan we would watch the waveforms of the front and rear 02 for diagnosis. When functioning properly the front 02 switches (low volts to high volts) fast the rear 02 switches slowly. So if I were to guess without seeing 02 data...bad cats.

Careful with cheap aftermarket cats as they may have low cerium content (an element that stores oxygen in the cat). Have put these in on sentra's only to have a false low oxygen storing code set...was ok when $$$factory cat installed.

right right the wave forms on the post cat 02s should be almost flat right, and if its wavy like the pre- cat 02s the cat is bad right. The things only got 68k on it, wouldn't i be seeing a major lack of performance though? if the cat was failing.

p.s. PCM was replaced under warrantty a few weeks back, could it just be a bad program?


is the a way to test the o2s's with a DMM, I've only had experience with a scope

the front 02 are used for fuel control. the rear 02 are for checking the cats only and are not involved in fuel control.

You would get performance issues with clogged cats or bad front 02 sensors.

Its possible that a lazy front o2 could set this code as the switching rates would be similar.

One senario could be good 02 sensors and bad cats (cat not plugged but rather just not oxidizing/reducing).

If your scan tool can monitor the 02 switching check the front o2; if switching fast at 2500rpm the 02 is good and the cats bad.

would this be covered under warranty typically?

believe usa had federally mandated warranty requirements for cats that extends past basic 3 years 60 000km bumper to bumper....someone else on this site will know.

50,000 miles or less / 5 years or newer