What causes a SPN 6223 code?

SPN 6223 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 6223 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 6223 active.

How do I fix SPN 6223?

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 6223

Cummins fault code 6223

What it means

Aftertreatment 1 Diesel Exhaust Fluid Doser Unit Current - Current Below Normal or Open Circuit. This indicates a circuit failure where the engine control module (ECM) detects that the DEF injector is not drawing enough current or is disconnected.