A more useful colored wiring diagram is provided here: a major thanks to @
Derek for making it.
http://www.ducatiscramblerforum.com/forum/electronics/9922-coloured-wiring-diagram.html
I've figured out what it does. It's a typo on the part of the manual. I've spoken with Ducati techs (informally) and more than likely not that is actually the diagnostic connector under the seat. When you take it in for service it is connected via a
proprietary Bluetooth dongle wirelessly to Ducati's new "DDS version 2.0". Previous DDS units required a physical wired connection to a specialized tablet, this new system appears to use a generic laptop over Bluetooth. So one step forward two steps back..... that software and dongle will
never be made for sale.
However, some dedicated people (myself included) are working on alternatives.
You mean like this? I already do that with my Ducati using a
FREE app for Android called ScanM5X made by a French gentleman named Christian whom I am good friends with. I assist him developing the app with the technical details -- to add AFR datalogging and support for these new ECUs.
He is an amazing individual and very humble about his work. He continually improves his app at no cost to the community at all. I humbly suggest donating to support his work:
[full disclosure, I have no part in this donation, it goes straight toward's Christian's research expenses (and wine fund

)]
[Donate to ScanM5X / ScanST]
No ETA on when M3C support will be added, as he currently has other pressing priorities at the moment and I am occupied with hardware issues.
A donation, perhaps even a few words of encouragement, may help shift his attentions this way.