What causes a SPN 2046 code?

SPN 2046 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 2046 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 2046 active.

How do I fix SPN 2046?

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 2046

SPN 2046 - SCR Chemical Reagent Level

What it means

This code monitors the Diesel Exhaust Fluid (DEF) level in the tank, indicating that the level has dropped below the minimum allowable threshold for proper aftertreatment operation.