While electronic groupsets have proven to be very robust in the field, they’re not immune to failures or issues on the more technical side of things. In this video I brick/destroy the Shimano Ultegra Di2 RD-8050 rear derailleur with nothing more than the Shimano E-Tube app…. and I go about restoring it back to working condition.
Note: Firmware restoration of individual components on non-working Di2 system will require the use of the PC Linkage Device (SM-PCE1 or SM-PCE2).

Just got a new Di2 group. The shift buttons are around the reverse way for my liking. So do I need the D-Fly unit to be able to talk to the group with the E-tube app and swap them? Or can it be done manually? So lost.
Use the charger to connect to the bike (via Junction A) and plug the USB end into a Windows PC. With the Shimano E-Tube app you can perform any reassignments you like.
Hi Shane,
Maybe of interest.
The new Shimano 12 speed wireless shifters need to be hard wired to update firmware. You cannot do it wirelessly through the app.
You will need to have access to the Shimano SM-PCE02 PC Interface and using the new cables EW-SD300 (smaller plug) with the EW-AD305 connector.
Information on Shimano’s website says you connect the Shifter to the rear derailleur, however this disconnects the power, I could not get this to work.
Note: You need to use the top port on the shifters for the connection to be established.
Thought this is something you may want to do a video on.
Cheers
Brad
I’ll get onto the new Di2 when I can get my hands on it. I’ve been told “August” for the new Ultegra Di2 group…… The alternate is to buy myself a bike with it… if there’s ever stock. Shimano not exactly making it easy for me to make tech content on their group.