What causes a SPN 3068 code?

SPN 3068 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 3068 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 3068 active.

How do I fix SPN 3068?

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 3068

SPN 3068 - Aftertreatment SCR Intake NOx Sensor Response High

What it means

Indicates that the Selective Catalytic Reduction (SCR) intake NOx sensor is reporting data that exceeds expected operating parameters for the current engine state.