What causes a SPN 2189 code?

SPN 2189 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 2189 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 2189 active.

How do I fix SPN 2189?

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 2189

J1939 SPN 2189 — Aftertreatment/Emissions parameter

What it means

Aftertreatment DPF Outlet Pressure sensor voltage is above normal. This indicates the voltage signal is too high, often a short to 5V or 12V.