What causes a SPN 801 code?

SPN 801 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 801 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 801 active.

How do I fix SPN 801?

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 801

J1939 SPN 801 — Engine Management parameter

What it means

Engine Control Module (ECM) internal software error related to engine management parameter configuration or out-of-range calibration data.