What causes a SPN 520250 code?

SPN 520250 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 520250 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 520250 active.

How do I fix SPN 520250?

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 520250

Quantity Control Valve(QCV) low side driver error

What it means

An electrical circuit fault on the low-side return of the Quantity Control Valve (QCV). The MCM has detected an unexpected voltage state or current flow on the return line of the fuel dosing solenoid.