A JCOM1939 Engineering Note on Error Handling, Bus Off, and Silent Mode in Two-Node CAN Networks JCOM1939.com | Copperhill Technologies | © 2026 Controller Area Network (CAN) is well known for its robustness. Arbitration prevents message collisions from corrupting data, error detection identifies damaged frames, automatic retransmission provides another opportunity…
Posts tagged as “CAN bus errors”
Designing a CAN Bus device that performs well under ideal conditions is relatively straightforward. The real challenge begins when the network no longer behaves as expected. In the field, connectors loosen, ECUs lose power, messages are delayed, wiring deteriorates, and configuration errors inevitably occur. A robust CAN device must continue…
If you’re learning SAE J1939, you’ll quickly run into two acronyms that show up everywhere—in diagnostic messages, simulation tools, engine logs, and OEM documentation: SPN (Suspect Parameter Number) FMI (Failure Mode Identifier) Together, SPNs and FMIs explain what went wrong and how it went wrong.They form the core of every…
If you’re new to SAE J1939, one of the first things you’ll encounter is how heavy-duty vehicles report problems. They do this using standardized diagnostic messages, and the two most important are: DM1 — Active Diagnostic Trouble Codes DM2 — Previously Active Diagnostic Trouble Codes Understanding these two messages will…
