How to connect your Di2 system to your Windows computer

Updated February 10, 2024 by BetterShifting

Modern Di2 is basically a couple of controllers and servo motors that communicate with each other using EW-SD300 or EW-SD50 wires. Shimano lets end-users configure their own Di2 systems using their e-tube project software. This page explains how to connect your bike to your computer.

12-speed Di2 - Wireless ONLY

If you have a 12-speed Di2 bike, then the preferred method is to connect to your bike using Shimano's mobile app. Wireless connectivity comes standard on 12-speed Di2 bikes, it is built into the rear derailleur.

Shimano's 12-speed bikes do come with a USB charger, but that can not be used to connect to the bike using the desktop E-Tube application.

The only way to connect a 12-speed Di2 bike to a Windows computer is using the SM-PCE02 diagnostics tool.

Personally, I wouldn't bother getting one - you probably don''t need it. The PCE02 is relatively expensive, doesn't charge the bike, and you can do almost everything you need to through the mobile app.

11-speed Di2 Road/MTB/GRX/Urban vs E-Bike

Connecting a Di2 bike to a Windows computer is done via the charging/interface port on the Junction A.

11-Speed Di2 road bikes, mountain bikes, and gravel bikes will all have this junction and the required interface/charge port. Some urban bikes will too.

However, STEPS E-bikes or E-MTBs generally use a display without this port. Also, most E-bikes use larger, external batteries and they do not come with the SM-BCR2 charger. If your bike is one of these I'm afraid you're out of luck - you can only connect your bike to a Windows computer using the SM-PCE1/SM-PCE02 diagnostics device.

Older road bikes with external batteries and the SM-EW67A junction can only be connected using the SM-PCE1/SM-PCE02 diagnostics device.

Locate the charging / interace port

You probably know where the charging port is - but just in case you don't, have a look at this image:

Di2 charge and interface port

Make sure you have either the SM-PCE1/SM-PCE02 diagnostics device or the SM-BCR2 charger. Also, download an up to date version of the E-Tube Project software.

E-Tube Project 3.4.5 - problem with the internet connection

If you've try to run E-Tube Project 3.4.5 recently, then you have probably gotten a rather confusing message:

There may be a problem with the internet connection or the Shimano's web server. Wait a little while and try again.

While it seems serious, you can actually still use the software. However, it won't download new firmware files from the internet.

E-Tube Project 3.4.5 was released in 2019, and it comes with firmware up to that period. Have a look at Shimano's firmware page to see whether or not there's newer firmware for your components.

E-Tube 3.4.5 there is a problem

So why would you use E-Tube Project 3.4.5 if version 4.0.4 works fine too?

You either have 10-speed components that you need to update, or you need to update the SM-BCR2 charger. See more on updating the charger further down this page.

In all other scenarios, I'd probably use version 4.0.4 instead.

IMPORTANT: E-Tube Professional

Note: E-Tube Project V5 / Professional does not work with the SM-BCR2 charger. You need to use E-Tube Project 3.4.5 or 4.0.4. Read the Faq page on this for more information.

The older E-Tube Project versions can be downloaded from the E-Tube Project archive.

Connect instructions E-Tube

Connect using e-Tube Project

Plug your charger into the junction box and connect the other end to your computer – the order doesn’t really matter, but I tend to plug the connector into the bike first. Start the e-Tube Project software. Then just click the 'Next' button.

E-Tube Project connect

If you haven't already, the software will tell you to connect your SM-PCE1/02 or SM-BCR2.

It’ll then tell you that charging has stopped because you’ve connected the bike to the computer and started the software.

E-Tube charging stopped

Also, it will tell you to use the disconnect button when you're done and then start unit recognition.

E-Tube for Windows connecting

When the connection has been made successfully you will be shown the Customize tab. This is where you can set up or tweak each component.

E-Tube Project customise screen

Cannot connect using the SM-BCR2? Need to update it?

When Shimano released E-Tube Project 4 they also introduced a lot of bugs. One of those actually prevents you from connecting to your bike using the SM-BCR2.

E-Tube Project displays a message, but won't actually update the SM-BCR2:

SM-BCR2 recognition. The process is interrupted because the version of SM-BCR2's firmware is old. Connect to the Internet and download the latest version of the firmware.

Now.. the workaround is relatively simple, if not a bit frustrating.

You need to download E-Tube Project 3.4.5 and update the SM-BCR2 that way. After that it's safe to use E-Tube Project 4.

E-Tube Project 3.4.5 can be found on the Shimano E-Tube Project site, or through this direct download link.

View installed components

Sometimes it is useful to see the list of installed components. When troubleshooting unresponsive components for example. By checking the list of installed and connected components you can figure out what part of the Di2 "circuit" is broken. Almost all components are listed on the Update tab.

E-Tube Project Update Firmware

If a component isn't listed here that means that it either isn't connected or it doesn't have any firmware that can be updated. Junction B (SM-JC41 / SM-JC40) and the external battery won't show up here for example.

Done? Use the disconnect button

When you're done please use the disconnect button as seen at the top left of the window. If you do not, the bike may not respond or may end up draining the system battery until you reconnect it. It isn't hard, but it is something to keep in mind.

Other things you can do with E-Tube Project:

Questions? Leave a comment or send me a message.


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