What causes a SPN 2794 code?

SPN 2794 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 2794 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 2794 active.

How do I fix SPN 2794?

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 2794

J1939 SPN 2794 — Aftertreatment/Emissions parameter

What it means

J1939 SPN 2794 (FMI 7 or 13 typically) refers to an Aftertreatment Configuration mismatch or abnormal update rate. It indicates that the ECM/ACM has detected parameters in the emissions system that are inconsistent with the vehicle's programmed configuration.