The LED of the button of the BPM can be:
- Blue if the BPM hasn't been paired with a mobile device yet.
- Green if the BPM has been paired with a mobile device.
- Orange if the previous measurement has failed. It then goes back to green.
https://support.withings.com/hc/zh-cn/sections/6215855075857-Wireless-BPM
https://support.withings.com/hc/zh-cn/sections/200529447-FAQ
