CR10S Pro display dead

I got the hot end and wiring straightened out on this printer and turned it on and the display is blank. It was working fine before. I did a no no and didn’t unplug the printer but it was turned off.
I hear the motherboard fan when I turn it on. I have checked that there is 24 volts to the motherboard. I don’t understand what could have happened. Any ideas?

Grasping at straws now. I reinstalled my old MB that was OK and I still have a problem. I have a Sonic Pad that installed Klipper on this printer and when I would plug in the USB, the display would light up, whether the power was on to the printer or not. Now the display is blank all the time.
The USB goes directly into the MB, so that’s why I changed the MB. Since I am using the Sonic Pad to control the printer, and the MB is getting 24V (tested), why would the display be needed at all and why if the display is bad would it affect the printer running?

Would a bad display board be the problem, since it is not used with the Sonic Pad? Could the breakout board be the problem, since that was the last thing I was working on? If so, how could that affect the Mother Board?

Any help, or suggestions are greatly appreciated. I have a Bambu Lab X1C but I want to get this printer running again. HELP please.

I found the problem with the help of tinymachines3D remote support. For some reason, Creality put a 3 pin connector on the daughter board for a 2 pin plug I had plugged the plug into the wrong 2 pins.