P2423: owner reports and bulletins

Powertrain (generic, all makes). We haven't written the explanation for this code yet. Below is what owners and manufacturers have filed with NHTSA.

Got P2423 on your scanner? Tell the mechanic your year, make, model and any symptoms and you'll get the likely cause and what to check first. Ask about this code.

What owners report to NHTSA

No consumer complaints filed with NHTSA mention P2423. That usually means it's rare, or owners don't quote the code when they file.

Manufacturer service bulletins that name P2423

1 technical service bulletins and manufacturer communications filed with NHTSA mention P2423, from 1 makes. A bulletin means the manufacturer has documented a known cause or a fix procedure for that model. Examples:

  • NISSAN ALTIMA (2010, 2011, 2012), bulletin 10173559: 2010-2012 ALTIMA; MIL ON WITH DTC P2423 NOTE: The warranty period for the front exhaust tube with catalyst (20010-ZX10A) has been extended on the Applied Vehicles if the following criteria are met: - The MIL is ON and DT…

Sources: NHTSA Office of Defects Investigation complaint database and manufacturer communications file, snapshots September 2026. A complaint or bulletin that mentions a code is a report about that vehicle, not a statement that the code has one cause.