What causes a SPN 737 code?

SPN 737 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 737 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 737 active.

How do I fix SPN 737?

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 737

J1939 SPN 737 — Engine Management parameter

What it means

SPN 737 indicates a 'Special Instructions' or 'Inconsistent Parameters' error within the Engine Management system, specifically relating to how the ECM interprets data from the vehicle network.