Home » Training » Trailer Glossary » SAE J1939 SAE J1939SAE J1939 is a set of standards that define how ECUs communicate via the CAN bus in heavy-duty vehicles. Click to share on Facebook (Opens in new window) Facebook Click to share on X (Opens in new window) X Click to share on Reddit (Opens in new window) Reddit Click to share on Pinterest (Opens in new window) Pinterest Click to share on LinkedIn (Opens in new window) LinkedIn