At the Microsoft forums a new thread states that after installing Windows RT 8.1 Preview the Surface RT tablet experience huge battery drain when in Connected Standby. Losing approximately 30% of battery juice during the day and when the tablet is not being used. The person posting the issue also details that using the powercfg /sleepstudy reports Microsoft UART V2 Driver (_SB.UAR3) as being the root of the battery problem. Shortly after a community member suggested to enable the Bluetooth wireless radio on his Surface. Although, such fix sounds backwards, because we all know that it can waste even more battery, this workaround actually fixed the battery drain issue currently in the operating system.
Instructions
If you are affected by the same problem try the following: from the Start screen use the +i keyboard shortcut, click or tap Change PC settings, go to PC & Devices, Bluetooth, and finally click or tap to enable the option. The community member also detailed the reasons of this strange behaviour: Apparently this isn’t an unknown issue for Microsoft in the preview version of Windows 8.1 on Surface RT tablets. The software giant will, on time, release an update to permanently fix this problem, but in the meantime, the workaround seems to solve the hiccup. A strange story with a happy ending… Update: If you are experiencing battery drain problems after installing the final version of Windows RT 8.1, Microsoft has recently published a new fix, you can find it here. Source Microsoft forums via Neowin All content on this site is provided with no warranties, express or implied. Use any information at your own risk. Always backup of your device and files before making any changes. Privacy policy info.