The screen does not work on macbook'13 without connecting an external monitor via HDMI, what should I do?

Question

macbook

Good day to all!
Faced the first serious problem for the entire time of operation of my macbook. What is the point:
The screen does not work on a 15th year macbook'13 Pro without connecting an external monitor via HDMI. If you turn on the laptop or wake up from sleep mode, the screen backlight does not work, Skype is loaded, the keyboard is lit, the screen is not. If you connect an external monitor, the regular one instantly turns on and works fine, if you pull out the hdmi, it instantly cuts out. It happened suddenly, it didn’t fall, it didn’t flood, there was no mechanical impact. Just after 1-2 hours of work the screen went out.
I tried everything I found on the Internet, incl. and on the apple forum, nothing helped. I reset NVRAM, rebooted, turned it on - turned it off in all sorts of different ways.
Good people, someone faced the same problem? Maybe someone also has a poppy from a reliable laptop turned into a disabled person? Tell me how to...

Answer 1

Maybe you have the brightness driven to a minimum?

Answer 2

I think you have a hardware problem, possible options: cable, matrix, motherboard. The logic of such a manifestation of the defect is approximately the following. The Mac cannot correctly identify the matrix. Some kind of signal does not come, there is a very confused connection, a DP matrix with a built-in backlight controller. The Mac cannot make friends with the matrix, therefore it does not show a picture, when you connect a TV set, it identifies it, the picture shows it and the logic of polling the built-in matrix changes. Already a smaller number of signals is being checked. Something like this, something like this) I had similar cases in practice. Diagnosing and localizing the problem is easiest by connecting another cover, bring me a free diagnostic.