Screen Back Light

lani193 wrote:

Please assist my Mac Book Pro 2015 Screen just went Black the laptop is on, when I use an external screen using a HDMI Cable am able to use it. is there anything I can do?

Well you can try

Try resetting NVRAM/PRAM http://support.apple.com/kb/ht1379

and no harm Try resetting the SMC https://support.apple.com/en-us/HT201295

But I suspect the display has failed, or the projector cable, or the connection— the way forward would be to repair the hardware issue.

Get your Mac ready for service - Apple Support https://support.apple.com/en-us/HT209095

Learn how to get your Mac fixed and how much it will cost.

https://support.apple.com/mac/repair/service

lani193 wrote:

I've tried that did not work thanks tho, I wonder what could be the cause of such.

?

display has failed, or the projector cable, or the connection

Plug it into an external monitor, if it works you know it is not the GPU.