What causes a SPN 5544 code?

SPN 5544 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 5544 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 5544 active.

How do I fix SPN 5544?

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 5544

Cummins fault code 5544

What it means

Aftertreatment 1 Hydrocarbon Doser - Mechanical System Not Responding or Out of Adjustment. This indicates the doser is unable to deliver the commanded amount of fuel into the exhaust stream for DPF regeneration.