The J1939 Diagnostic Manager (DEM), in conjunction with ssJ1939-Multi, serves as a database and framework for managing J1939 diagnostic messages. It facilitates setting, clearing, and storing freeze frame data, and transmitting DTCs in accordance with the J1939-73 specification. The module also processes and responds to inbound request PGNs.

Supported Diagnostic Messages (DMs) include: DM1, DM2, DM3, DM4, DM10, DM11, DM12, DM13, DM14, DM15, DM16, DM30, and DM31.

Additionally, the DEM can be integrated with an NVM module to permanently store all faults and freeze frame data, enabling fault retrieval throughout the vehicle’s lifespan.