What causes a SPN 520332 code?

SPN 520332 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 520332 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 520332 active.

How do I fix SPN 520332?

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 520332

Selective Catalyst Reduction (SCR) Inlet Temperature Too Low

What it means

The Aftertreatment Control Module (ACM) detects that the exhaust temperature entering the SCR catalyst is below the minimum threshold required for proper NOx conversion.