Ultegra Di2 Rear Mech Stopped Working

mathuna11

Ultegra Rear Mech Di2 just stopped working midway down the cassette and wont move now. I checked all the connections and even plugged in from a different power supply so the issue is definitely the mech and it is only a few weeks old. I can bring it back to the LBS but I said it try myself first if its something small.

Koobcam

Hadn't heard of this issue before, usually you hear about batteries dying mid-ride because people forgot to charge up their Di2. Didn't Sagan get stuck in the small ring at Paris Roubaix because his front mech wouldn't shift? I'd say just bring it back to the shop and let them sort it out, it's a fairly expensive bit to be fiddling about with.

Inquitus

mathuna11 wrote: »

Ultegra Rear Mech Di2 just stopped working midway down the cassette and wont move now. I checked all the connections and even plugged in from a different power supply so the issue is definitely the mech and it is only a few weeks old. I can bring it back to the LBS but I said it try myself first if its something small.

There's a connection in the bottom bracket, are you sure that's not where its become disconnected?

lennymc

Lumen

Koobcam

Lumen wrote: »

Jaysus, think I might wait until Sram come out with their wireless shifting system after looking at your diagram.

mathuna11

Yes checked all that and I swapped the mech for another one and that one worked so its an issue with the mech.

Lumen

Koobcam wrote: »

Jaysus, think I might wait until Sram come out with their wireless shifting system after looking at your diagram.

Yeah, because wireless systems are way easier to fix :pac:

Mugser

Did you press & hold the button on the junction box, while turning the crank? Its a re-set function.

G2ECE

Is it ok if I piggy back on this thread??

Ultegra 6870 di2 rear mech stopped working for me but I noticed the cable was pinched, ordered a new cable but still didn't work. Front mech working fine at this point.
I then downloaded E-tube project and connected the bike hoping to do a diagnostic, at this point it only recognised the LH shifter (for front mech), so I was now putting my issue down to a faulty switch in the right shifter or else the junction box under the stem. e-tube project then prompted me to update the firmware for the battery and the junction box, which I duly did. Now e-tube project does not recognise the unit connected and I have absolutely nothing movement in either mech at all and no lights working on the junction box. all parts are Ultegra di2 6870, no mash up of different parts. has anyone experienced this or does anyone have any suggestions?

Thanks in advance,
G.