What causes a SPN 23 code?

SPN 23 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 23 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 23 active.

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 23

J1939 SPN 23 — Engine parameter

What it means

Engine Rack Position sensor error. This older protocol code usually relates to the mechanical fuel rack position or governor feedback.