What causes a SPN 2931 code?

SPN 2931 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 SPN 2931 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 2931 active.

How do I fix SPN 2931?

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

J1939 SPN

SPN 2931

J1939 SPN 2931 — Aftertreatment/Emissions parameter

What it means

Aftertreatment/Emissions Parameter 1 - Data Erratic, Intermittent, or Incorrect. This SPN typically points to a communication or electrical integrity issue within the SCR system components.