GP's point was not that manufacturers must use github - that was an arbitrary "for instance". They saying if the mfg is not going to open source their software, then they should be required to document it.

Certain PID values are bit-packed in non-obvious ways (like the tens digit is in one byte, ones in another, decimal in another) and units of measure are 'known' but might not be obvious. Publishing that information (which already exists! How do you think they write software?) would be a nice step in the right direction

J1939 is really all most consumers need to care about when it comes to their personal car CAN data.

https://github.com/Konik-ai/j1939_dbc/blob/main/dbc/j1939.db...

There are a ton of dbc files floating around like this. Almost any car with a turbo has a kit to flash the ecu for more boost, so even the proprietary signals have been reversed.

That's just BCD, which these days is transparent with AI.

> I can poke at OBD and try to interpret values. CAN bus sniffers exist.

Ghidra exists. That doesn't mean all software is open source.

> You want to force companies to publish and maintain repositories using your preferred toolset?

Nope. Anywhere will do, whatever is easiest for them, as long as device owners can access it.