[SOLVED] Laptop screen very dim after 5-10 sec of boot up

[Ravidaada]

I have hp pavillion M6 laptop. When I boot it , it normally starts, display, keyboard are working good but after 5-10 sec display goes very dim that I can't see anything and no key works with keyboard. However external monitor and keyboard works well.
Same thing happens with recovery screen, bios setup , safe mode etc. At first everything works fine but after a while screen and keyboard are not responsive. I have windows 10. Checked ram by replacing then CMOS battery voltage is accurate. Nothing works. Please help me.

 

[whateverami]

If you hooked up an external keyboard then control the brightness of your laptop from there or use windows's built in brightness control.