What causes a SPN 4424 code?

SPN 4424 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 4424 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 4424 active.

How do I fix SPN 4424?

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 4424

Cummins fault code 4424

What it means

Aftertreatment 1 SCR Temperature Sensor - Abnormal Update Rate. The ECM has lost communication or is receiving invalid data from the SCR temperature sensor module via the J1939 data link.