What causes a SPN 928 code?

SPN 928 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 928 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 928 active.

How do I fix SPN 928?

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 928

J1939 SPN 928 — Engine Management parameter

What it means

Engine Management Parameter. This code indicates a mismatch or error in the programmable configuration of the Engine Control Module (ECM) or a specific software parameter out of expected range.