di2 6870 rear derailleur doesn't work, junction box doesn't show lights
My rear derailleur stopped working in the middle of a ride yesterday. Nothing happened, no crash, it just stopped working. The 'junction a' box doesn't seem to respond to button presses either. I can shift the front derailleur just fine. I've tried clearing crash mode, I've tried leaving it unplugged, and I've tried charging it, no change. I tried using E-TUBE via windows but it failed to connect BUT it was my first time trying to use it so its possible that there's something wrong with that setup. Disconnecting the rear derailleur does _not_ restore junction box a functionality.
At this point I lean toward a battery or junction box problem.
Any tips on resolving this? I'm out of ideas.
Last edited by mattkime; 06-17-22 at 07:05 AM.