Battery State and OS Upgrade
A fully charged main battery must be cabled to the HX2 prior to reflashing or upgrading the operating system. A prompt may appear when the battery reaches Critical Low that informs the user there is not enough power in the main battery to perform the upgrade.
The operating system will not be able to execute the OS update when the battery level is too low (25% or less), as there is a high risk that the power remaining in the battery expires when executing the upgrade and the HX2 will be left in an inoperable state.
When main battery power level is too low, connect external power to the HX2 before performing the upgrade procedure. Do not disconnect external power before the upgrade process is complete.