Don’t be as dumb as me. Do not ever update your Shimano Di2 from a phone that is low power mode. If you do and the lock screen comes on, then the Bluetooth LE connection gets interrupted and the Shimano Di2 shifting system hangs. It won’t even shift or respond. This is a super common problem.

Here is what happened (I’m so stupid) and here’s what to avoid and the some fixes I tried before going to the local bike shop praying:

1. Do not update this firmware! Shimano may make really reliable hardware, but firmware updates are not its thing. If you really are going to do it make sure your iPad or iPhone are charged up and you do not have it on lower power mode, if the application loses foreground, it will hang up the connection.
2. Here is how I got here, if you have an older Di2, then you have to buy a bluetooth transmitter. The default is to use a special USB to Shimano connector as a laptop to do this. But I bought and also the magic $4 tool that makes it easy to pull the connector apart and assemble it.
3. Here’s a note on how to do it. First push the button all the bottom of the junction box briefly. This should cause the lights to flash red and green alternatively.
4. Now load the eTube application on your phone or iPad. When you load it will say connect via Bluetooth LE. As an aside, this is not the same as the Bluetooth connection you normally make, it happens in the application.
5. If all goes well, it will detect it and ask for a passcode. The default is 000000 and I would change it. If you do make sure you note it somewhere as you can get stuck without it.
6. Now you will have a bunch of options and one will be firmware update. Here is where I made my stupid mistake. The firmware update is for each component and it was asking to update the main junction box. This takes several minutes and as I was waiting, the lock screen came on. This is absolute disaster because the Bluetooth LE connection hangs up and now the shifting system is completely dead. It doesn’t even show charging on the system any more and certain doesn’t shift. So if you are doing this make sure you never get into lock mode while doing the update.

Recovering by disconnecting For newer models

Well, the main piece of advice is to reverse the installation and disconnect all the wires, this power down is supposed to fix the bad firmware problem. This works for later versions of the di2

1. Disconnect the front derailleur, the rear derailleur and the shift levels and the battery. This is supposed to cause a reset of the whole system.
2. The front derailleur connection is at the top and the little Shimano tool has an open end you can use to grab and pull. Then to put back in, you use the open end and push. You should hear a click.
3. The rear derailleur is also pretty easy as well, it’s also on the side.
4. The front system has a junction box Called the A box, it has three connections. The left and right shifter and the the center one that goes to the bluetooth and then to the battery, you just have to disconnect each one and click to plug it back it.
5. At least for me, this didn’t really work. When I plugged in the power, at least I did get an orange light indicating that charging was happening, the the shifting didn’t work and the lights were totally dead.

Wired connection for older models

For di2 versions from three years ago, You can use the wired connection to connect a Windows machine to it. I had forgotten how confusing it is to install Windows applications, but here’s a guide;

1. Go to the Shimano site and download the Windows application called e-Tube.
2. When you try to run the installation, it will say on Windows 10, you need to install “Microsoft .NET Framework 3.5”, but it isn’t clear where this lives
3. At least on my Surface Pro, the lower left search entry doesn’t work. You get Cortna starting, but window sizing isn’t right, so you can read the screen.
4. I finally was able to get settings and do a search for “Windows Features” and you click on Framework 3.5 and it tries to load some Windows Update components.
5. This then fails saying it was unable to download and you are stuck.
6. After doing a reboot, this all worked. Windows does seem to require reboots.

Off to the Local Bike Shop

Well, I’m the local shop and hopefully they can fix. Again, don’t be as dumb as me!

They were able to get it working again by rebooting the system with the wired connection. So you’ve been warned.

Apparently this is quite common.