What causes a SPN 545 code?

SPN 545 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 545 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 545 active.

How do I fix SPN 545?

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 545

J1939 SPN 545 — Engine Management parameter

What it means

Engine Management Parameter / Engine Brake Control circuit fault. Indicates a failure in the circuit used to control engine retardation or general engine management auxiliary functions.