What causes a P229F code?

P229F can be triggered by several issues — see the verified probable causes and step-by-step diagnostics shared by mechanics and owners on OBDIY.

Can I drive with a P229F code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with P229F active.

Follow the step-by-step diagnostic on this page, then read the verified fixes contributed by other Heavy Truck owners — the answer marked "Verified Cause" worked for the original poster.

OBDIY

Log in Sign up

OBD-II

P229F

NOx Sensor 2 Circuit Range/Performance

What it means

The downstream (outlet) NOx sensor is reporting values that do not align with the SCR efficiency model.

Sign in to view symptoms, probable causes, diagnostic steps, severity, and related codes

Log in Sign up free