What causes a SPN 935 code?

SPN 935 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 935 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 935 active.

How do I fix SPN 935?

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 935

J1939 SPN 935 — Engine Management parameter

What it means

SPN 935 indicates a communication or data integrity issue related to the Engine Management transmission over the J1939 network. It typically points to the ECM's inability to broadcast or receive specific engine configuration or performance data parameters.