Ultegra Di2 rear mech just stopped working?

JesseD

Mid ride this morning my rear Di2 mech just stopped shifting, the front is working fine and the battery is charged as far as I can tell, the light on the box under the stem lights green when I press both shifters at the same time.

No wires are loose as far as I can see, it's simply stopped?

It's only 6 rides old?

Anyone had this, easy fix, what do I need to do?

meanredspider

If the right shifter is causing lights on the junction box, then it is working and connected. That limits the problem to the RD or the wire to it. I'd disconnect and reconnect the RD. To confirm it's the RD, try connecting the FD to the RD wire.

JesseD

I think I have it narrowed down to my right shifter, when I hold down the shift button on the left shifter the battery status light comes on full in green, but when I do the same with the right shifter I get nothing?

All wire are connected properly so I can only assume it's the shifter?

meanredspider

Are you certain the cable is properly connected with a full click? They are difficult to connect properly. LBS did mine when wrapping bars and neither was properly done. The tool is pretty much essential. Have you tried both levers for the battery check? If neither works, I'd still be putting my money on the connection. There's really very little going on in the shifter so it seems unlikely to fail mid-ride without an off.

JesseD

Yeah it's very strange, I was on the flat and the shifting just stopped on the rear mech, no crash, nothing?

The left works and lights up the battery light on the junction box under the stem but nowt from the right shifter?

Might just have to take it in to the LBS where I bought it and let them sort it!

Another question I have is the charging light on the charge box lights up when charging but for 5 seconds then goes out, is this normal?

meanredspider

IIRC the charge light going out says the battery is fully charged - but I never remember.

JesseD

Great thanks for your advice meanredspider

mikecassie

It could be the wire connection in the shifter, I found mine was not fully clicked in when I changed the tape on my handlebars. It still worked fine but the wire had been installed quite tightly and maybe a small bit of pressure could've moved the wire under the bar tape. It would be best to remove the tape as if it is this then just forcing the connector back in might be too much for the small wires in the cable.

JesseD

mikecassie wrote:

It could be the wire connection in the shifter, I found mine was not fully clicked in when I changed the tape on my handlebars. It still worked fine but the wire had been installed quite tightly and maybe a small bit of pressure could've moved the wire under the bar tape. It would be best to remove the tape as if it is this then just forcing the connector back in might be too much for the small wires in the cable.

Took it into my LBS this morning on the way to work and he said the same, we unwrapped the bar tape and freed the wire from the electrical tape holding it to the bar and took the wire out of the connector in the shifter and then clicked it back in. He then placed a small loop of the wire on the side of the shifter before taping it down to the bars again and hey presto this worked! Apparently the twisting on the var tape when climbing can un-click the cable enough for it to break the circuit so by adding this small loop it allows for any pressure etc.

It now works fine so I am going to do the same to the left shifter when I get home.

meanredspider

Good. Despite what some say, most Di2 issues are very easy to fix and are often just down to poor installation.

JesseD

Completely agree, he did say whoever wrapped the tape should have done this and when I changed the bars I simply copied what had been done by the shop.

At least I have a working shifter again now as I have a 3 minute climb 500m from my house which I have to go up every day before I am warmed up, the length of the climb itself is not an issue, however it averages between 10-12% and tops out at 18% so when you are climbing in 36x17 it hurts

pippi_langsamer-2

The Di2 installation instructions specifically tell/ show you to make that little loop with the wire as it comes out of the shifter hoods. As explained, it eliminates any pull on the cable disconnecting the plugs...