Thanks for responding to my problem.
TX & PX I connected correctly. USB to RC232 converter is tested on other devices.
when connected to the power supply, the device does not boot
yes my Khadas does not power USB ports for a USB mouse
Voltage AO_5V normal.
fuses F1 (500mA) and F2 (900mA) are OK
VCC5V is missing
HDMI_5V_EN always 4.9V
Also, my laptop does not see it when I try to launch a firmware update (while holding the power button while connecting to USB)
for power, I used a proven power supply, applying a voltage of 5V to the DCIN input and using a regular monitor. With this connection option (external power supply), it worked for more than two weeks.
I could not confuse the polarity, because I use the connector with the keys
after what happened, I specifically once again checked the power supply for possible power surges when switching on and off. But found nothing - the power supply is working fine
Maybe u try to reinstall the USB Burning Tool on your Windows PC. I have faced this problem before. I just reinstall the USB Burning Tool and plug usb to my VIM2. And that’s it. I didn’t use the MRegister mode.
Yes, my VIM2 device worked fine when I received it.
I originally used a power supply via USB-C.
when I got the cable I connected the power through the VIN port
For almost a month after switching the power on to VIN, it worked perfectly for me, but it did not suddenly turn on.
Not sure if you connectted the VIN port in wrong way and demaged the device, as from the videos you posted, the white LED light on just a moment if you press the power button or plug-in the DC, it’s not a normal and should be power issues.
If you still cannot locate the issues, you can contact the customer service for the return details.