HP 14-dw1025ns Keyboard, touchpad and backlight do not respond

Hello everyone.
I have an HP 14-dw1025ns with motherboard 6050A3202801-MB-A02, which was working fine. After turning it off and on again, the screen backlight stopped working, and the keyboard and touchpad also stopped working.
If I connect it to an external screen, I have an image. And on the laptop screen I also have an image but without backlight.
The computer works without problems when connected to an external screen and with a mouse and keyboard via USB.
I have removed the motherboard, and I have visually inspected it but I don't see anything strange.
Through Windows, I have updated the BIOS to the latest version, but everything remains the same.
On the keyboard, the only key that responds is the power button
When the computer is working and turns off. If I try to turn it back on, it does not respond to the power button. You have to wait or hold the button down for a few seconds, release it and press it again. Or if I remove the battery and power and reconnect, then it responds immediately

Is it possible that a defective U300 is responsible for the 3 failures?

Measure the voltages on pins 1, 20, 22, 28, 29, 34 of CN3000.

Pin 1 ... 3,32V
Pin 20 ... 13,20V
Pin 22 ... 3,3V
Pin 28 ... 3,3V
Pin 29 ... 3,3V
Pin 34 ... 3,3V

Any other suggestions? Are the voltages correct?

Measure the voltages to ground on pins 16, 17 of LVDS connector CN3000, when the machine is turned on with the internal screen connected.

Finally, this customer decided to pick up the laptop, because he needed it urgently and couldn't wait.

I'm locking the topic, as I can't make progress.