What causes a SPN 2438 code?

SPN 2438 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 2438 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 2438 active.

How do I fix SPN 2438?

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 2438

J1939 SPN 2438 — Aftertreatment/Emissions parameter

What it means

Exhaust Gas Temperature (EGT) Bank 1, Unit 2 circuit signal is erratic or outside normal operating parameters. This usually refers to the sensor located after the Diesel Oxidation Catalyst (DOC).