This makes it very hard to troubleshoot things without paying for an interface or product that is certified and understands all of the data on the network. For example, the NMEA publicizes which messages exist and which fields they contain, but they do not disclose how to interpret the values contained in those fields.“ “ NMEA divulges some information regarding the standard, it claims copyright over the standard and thus its full contents are not publicly available. The bigger challenge in troubleshooting data on the network is actually the body that governs it – NMEA. It’s not the best network in the world, and has a lot of drawbacks and issues, but it is the standard we have to deal with for now. CAN was released in 1986 with NMEA 2000 coming in the late 1990s, so it is already nearly 20 years old, and based on 30+ year old technology.

NMEA 2000 networks are electrically similar to a Controller Area Network (CAN) bus network which can be found on cars and trucks.

Software is more complex and expensive, but can help diagnose device configuration issues. Most people should start with a hardware method to ensure the basic electrical properties of their network are sound. There are two main ways to troubleshoot a NMEA 2000 network – hardware and software. Troubleshooting an N2K network can be done very easily. NMEA 2000 networks are part of any connected boat, and can be problematic by nature of their design.

Nmea 2000 network setup book