Windows 10: THinkpad 10 tablet keeps providing usb power??

Windows 1903


Hello again,



I am attempting to use my thinkpad 10 tablet ( Windows) as a car front end.



I am getting there ( *Smile ), but am still stuck by some problems.



One of these is power management.



I have various peripherals connected via a separately powered usb hub.



so........ I don't need any power to the hub from the tablet.



If I am not going to be away from the car for long, rather than shutting down the tab, I sleep it .



Althougth power to the tab and the powered hub is removed, the tablet still gives power to the hub from its battery reserve.



The hub has seven peripherals attached, so it can represent quite a drain to the tablet on battery.



I have tried to prevent usb ( selective suspend), and also tried to check for windows powering down any usb devices to save power in Device Manager.



Still, every time the car removes power, the usb port on the tablet is still active??



Has anybody any ideas?



-- by the way, I have no option in BIOS for usb power, and I also tried to make a USB cable DATA only- no luck ------



Many Thanks

:)

 

THinkpad 10 tablet keeps providing usb power??

Windows 1903


Hello again,



I am attempting to use my thinkpad 10 tablet ( Windows) as a car front end.



I am getting there ( *Smile ), but am still stuck by some problems.



One of these is power management.



I have various peripherals connected via a separately powered usb hub.



so........ I don't need any power to the hub from the tablet.



If I am not going to be away from the car for long, rather than shutting down the tab, I sleep it .



Althougth power to the tab and the powered hub is removed, the tablet still gives power to the hub from its battery reserve.



The hub has seven peripherals attached, so it can represent quite a drain to the tablet on battery.



I have tried to prevent usb ( selective suspend), and also tried to check for windows powering down any usb devices to save power in Device Manager.



Still, every time the car removes power, the usb port on the tablet is still active??



Has anybody any ideas?



-- by the way, I have no option in BIOS for usb power, and I also tried to make a USB cable DATA only- no luck ------



Many Thanks

 

THinkpad 10 tablet keeps providing usb power??

Thanks Ed,

I don't think it is dedicated- doesn't mention it in any manual, and it is not coloured yellow.

The tablet BIOS is restricted and doesn't contain any USB power settings.

I guess I could be pragmatic, and measure how much battery drain I get from being out of the car for, say, two hours ( MAX), and if it is less than say 30%, just live with it*Smile

Unfortunately, hibernation doesn't work with my set up, which would have been an answer.

Thanks again

 

THinkpad 10 tablet keeps providing usb power??

Some USB ports are configured to deliver juice until the battery goes dead. They usually have yellow plastic inserts, and are known as "Always On USB" ports (here's an informative SuperUser discussion of this topic: How does "Always On USB" work?). It might be that this port is set up for or stuck in this status. Usually requires a BIOS change to alter such behavior.
HTH,
--Ed--