What causes a SPN 945 code?

SPN 945 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 945 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 945 active.

How do I fix SPN 945?

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 945

J1939 SPN 945 — Engine Management parameter

What it means

J1939 SPN 945 refers to the Engine Management System receiving or requesting parameters via the J1939 data link that are missing, invalid, or corrupted.