How do you replace a Di2 wireless shifter battery?
12-speed wireless di2 shift levers (ST-R9270/ST-R8170/ST-R7170) run on CR1632 batteries.
These batteries will last for about two years, and will eventually run out.
To check the battery charge left, simply press both shift buttons at the same time. The LED on the lever hoods will then indicate the remaining charge.
- Green: 11% to 100% battery
- Red: 1% to 10% battery level
- Off: 0%
I've written a guide on checking and replacing the shift lever battery, and I've added links to CR1632 eBay/Amazon pages at the bottom of the guide.
Is video more your thing? Here's a quick video on replacing and checking the battery.