What causes a SPN 290 code?

SPN 290 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 290 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 290 active.

How do I fix SPN 290?

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 290

J1939 SPN 290 — Fuel/Air parameter

What it means

SPN 290 corresponds to the Fan Drive Signal or Fuel/Air Ratio related configuration, depending on the specific OEM proprietary implementation (commonly associated with Fan Drive state on many platforms).