Question Laptop screen goes black after disconnecting from power

[TomasLTU]

Hi, got a problem with Asus laptop. Unplugging the power cable results in black screen, but the laptop is still on.
Laptop model: F555LB Series. Windows 10 64 bit. Battery is new. No Warranty.

Stuff that i tried:
Updated all drivers with Driver Booster app.
Nvidia Drivers updated.
Tried changing every power option. Some Options were missing like Brightness when Power cord is unplugged or Screen Refresh rate in Intel HD Graphics settings.
Pressing Brightness buttons wont do anything (Works when the power cable is in).

I tried connecting Laptop to other Monitor using HDMI and everything works with or without power cable, but couldnt get 2 screens working at the same time. Only external monitor was working. Tried to change settings like Duplicating or Extending monitor but nothing.

Resetting Windows didin't do much either. The Laptop came with Windows 8, i upgraded free to Windows 10 few years back. My thoughts are that Windows 10 is making the problem but can't find any sollution.

Any ideas would be grateful.

 

[my_pc_build]

Hi TomasLTU,
how annoying. Can you test the battery at all? I read that it's new but wonder if its output (unplugged) is such that the os decides it can't provide enough power to keep the screen on.
Not sure where you bought it but if it's new and faulty surely you are entitled to a return or exchange.

All the best.

 

[TomasLTU]

Hi TomasLTU,
how annoying. Can you test the battery at all? I read that it's new but wonder if its output (unplugged) is such that the os decides it can't provide enough power to keep the screen on.
Not sure where you bought it but if it's new and faulty surely you are entitled to a return or exchange.

All the best.

Well the battery can support external monitor or even the TV connected via HDMI cable. Using external monitor i can see stable battery time not dropping rapidly down.

 

[my_pc_build]

Hmm, still worried it might be a problem with the new battery. A few users reported success with the following (https://www.ifixit.com/Answers/View/379051/Computer+screen+blank+out):
I fixed this problem recently. The laptop screen was very dark, yet I could see everything on an external monitor (hdmi cable in this case) and if I used my lamp on the phone close to the screen, I could see everything.
I simply pulled out the battery cable, turned off the computer, then held the start button for 30 seconds (despite starting, keep it in, it will shutoff the computer after a while, and keep counting to 30 seconds from the starting point). Your battery should be empty by now. Attach the battery cable to the computer, and start the computer again.
Comment below the above seems relevant:
It appears that the battery is failing and needs to be replaced. The laptop’s power management system is prioritising the power distribution in the laptop and probably turning off the backlight to the display to ensure that other functions are still being maintained.

Good luck

 

[my_pc_build]

Well the battery can support external monitor or even the TV connected via HDMI cable. Using external monitor i can see stable battery time not dropping rapidly down.

Can you confirm that the specs on the battery are correct for your laptop? Can you put a multimeter on it?
Sending video output to an external monitor / TV won't require anywhere near as much wattage / amperage as powering the laptop's own screen.

 

[TomasLTU]

I will try it tomorrow. Now other problem is that my mother spilled tea over laptop and it doesn't recognize HDD at boot...