What causes a SPN 3677 code?

SPN 3677 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 3677 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 3677 active.

How do I fix SPN 3677?

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 3677

J1939 SPN 3677 — Body/Chassis parameter

What it means

This code indicates that the J1939 network has received an invalid or inconsistent parameter value specifically related to body or chassis integration (likely out of range or misconfigured).