What causes a SPN 3063 code?

SPN 3063 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 3063 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 3063 active.

How do I fix SPN 3063?

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 3063

SPN 3063 Aftertreatment Selective Catalytic Reduction (SCR) Dosing Unit Heater Control

What it means

Indicates a fault in the control circuit for the SCR dosing unit heater, often related to open circuits, short circuits, or heater element failure.