Black screen after disassembly, both Joycons vibrate once(AutoRCM)

I need your help. I took apart my Switch to change the Motherboard into a switch in better condition.
I aborted that mission, too complicated, no steady hands. Went through the iFixit guide till the speaker connectors. Didnt get those out.
Now if i start it, the backlight turns on, the payload (hekate) gets injected. Both Joy Cons vibrate once.

But there is no display. It stays black, the backlight stays on.

I took it apart again but it didnt change anything.

Do you have any tips where to start, where to end?
It should work because it did before. But it doesnt.


Most likely an issue with the LCD connector. They are very easy to damage when plugging them back in. Have a close look to see if there are any bent pins.