[Teclast X98 Air 3G] 1KeNnY1KeNnY1:
Tablet doesn't charge when ON

Hello friends,

now I have interesting new issue, that I don't know how to fix.

The tablet doesn't charge when is turned ON.

I have got the HG6N version of Teclast X98 Air II tablet, the Windows 8.1 version only, for a month, it was running with no issues at all, only sometimes at beginning before Windows Updates it restarted or turned off when put in charger.

Recently I have bought an powered USB Hub, like I have "reviewed" in this video youtube.com/watch?v=ZrGuTd74KT8

So here is scenario from that day, I waited till 15% battery so I can make a video of charging it.

So first I connected the HUB to Charger and then to tablet. Was not charging. Was connected but not charging. Ok I thought not this way, so I connected the HUB to Tablet and then to Charger, and After that I think it started charging (or vice versa). But it was charging on about 3,6 Watts. When the video was finished, I disconnected it and connected it to my normal charger, charging normally 7,4 Watts. I left it be for 4 hours for full charge.

Now here it becomes interesting.

I came to the tablet after 4 hours, Checked the status and it was 97% Connected but not Charging (0 Watts, no Charge). Interesting, I removed the USB cable, waited few seconds, connected the USB cable again, but nothing. Ok, I though maybe I need restart, so I removed the cable, and used the tablet for whole day, some restarts, full turns off (I have disabled hibernation).

After 10 hours, was midnight, and I had again 15% battery, so I went to bed, and put the tablet, in windows desktop, wifi off, on charger, but, nothing. It didn't recognize the cable from charger connected (I am still using the same Charger I did last time 2.1A external). Hmm, so I restarted the tablet, but nothing, even when connected chargers, simply it didn't signal that it is charging. Ok so I tried the stock factory adapter charger, nothing, tried different cables, total 5, nothing. Tried xiaomi power bank where are leds indicating that it is charging. Nothing. ok So I turned off the device, as I was reaching 10% of battery . When the tablet was turned off, I connected the charger, and left it be for 20 minutes, while that I was searching what the hell is going on. After 20 minutes I turned on the tablet and it was 18% charged, so I know it is charging the tablet (BUT NO SCREEN ON BATTERY or something, simply the screen did not activate). In Windows it doesn't charge.

I read the forums, that Windows could have issues with charging the battery, so I removed the "Microsoft ACPI Compliant Control Method Battery" from Device Manager restarted tablet (after that it reinstalled the driver again), with connected, unconnected charger, everything, simply the tablet will not recognize that it is plugged in and does not charge when system is on.

The USB works well, when connected devices, like flash disk, keyboards etc.

After 2 hours of tries, I simply turned off the tablet, connected my Xiaomi Power Bank 16000mAh, and I seen it is charging so I left it to full charge at night.

In the morning I see that Xiaomi Power Bank turned off, that means the tablet is fully charged.

Disconnected the Power Bank and turned on the tablet.

In windows I have seen 100% battery, so it charged fully with no issues while was off. So that means, the connection to battery is there, and that charging is working, so the problems has to be with Windows or UEFI BIOS.

Checked the UEFI Bios, only I have seen an S5 charging disabled, but don't know if it was always disabled so probably someone can check what status they have?

I tried something more with the Xiaomi power bank, I tried after 1 hour, when the battery on Tablet was around 85%, to force charge it in Windows (the power bank it should start charge automatically when connected, but when you turn on the Button it will force charge) it blinked for few seconds, indicating charging, but nothing displayed in system, and turns off charging. I turned off my device, and it started to charge immediately. I turned on my device, after the windows loading screen finished, the charging stopped. So Definitely an Software issue.

So first I tried Refreshing the System, and then full system restore. Nothing helps. Still doesn't recognize the charging when the device is on.

So now I don't know what to do, reflash the bios ? Will I be able to when the charge doesn't work when system is on ?

Does somebody here had similar issue ?

Thank you for all the help and tips.