Shimano Di2: charging, shifting, and setup guide

Shimano Di2 makes electronic shifting simple, reliable, and easy to customise. Here’s everything you need to know about charging, shifting, and setup. 

Charging your Di2 system

• Plug the Shimano charging cable into the front junction box, with the cable pointing upwards.

• A blue LED confirms charging has started.

• Handlebar shifters use button cell batteries (CR1632). These don’t need charging and typically last 2–3 years before needing replacement.

How to shift with Di2

Right-hand shifter (rear derailleur):

• Small inner button = shift to a harder gear (smaller sprocket).

• Large outer button = shift to an easier gear (larger sprocket).

Left-hand shifter (front derailleur):

• Small inner button = move to the small chainring.

• Large outer button = move to the big chainring.

Checking battery levels

Shifters

• Hold down both shift buttons.

• LED at the lever shows status:

  • Green = good

  • Red = low battery

Main system battery

• Press the function button on the front junction box.

• LED shows:

  • Solid green = 100%

  • Flashing green = ~50%

  • Red = charge soon

  • Flashing red = very low

Using the Shimano E-TUBE Project app 

The E-TUBE Project app lets you:

• Customise shifting behaviour

• Run firmware updates

• Adjust button functions

• Monitor system status

Extra features for Ultegra & Dura-Ace Di2

These groupsets include top buttons on each shifter. You can customise them in the E-TUBE app to:

• Shift up or down the cassette

• Control accessories

To set them up:

1. Open the E-TUBE app.

2. Select your bike and shifter.

3. Assign your preferred function to each top button.

Need help?

If you’re unsure about charging, shifting, or setup, our Customer Service team is here to help you get the most from your ride.