Steam Support
An error occurred trying to handle that request. Please give us a few minutes and try again.
Steam Support
Sign in to get personalized help for Steam Controller.
You selected the issue: System button doesn't light up

If you see no light but you can still play games, you can adjust your Steam Controller's light intensity from the Controller settings menu in Big Picture Mode.

Remove batteries and connect with micro-USB cable
Remove the batteries and plug the Steam Controller into your computer's USB 2.0 port using the micro-USB cable.
If one USB port doesn't work, try a different one.
Replace the batteries
Unplug the Steam Controller and replace both batteries.