Problem with RT-AX92U booting

[d.mon1984]

Hi.

The problem is as follows. After pressing the power button, the LAN light comes on, but the POWER light does not come on.
Connecting via UART - silence.
Maybe one of us has experienced similar problem.
I would appreciate your help.

 

[L&LD]

Welcome to the forums @d.mon1984.

Have you tried with another power supply? These are cheap units and are known to fail.

 

[d.mon1984]

Welcome to the forums @d.mon1984.

Have you tried with another power supply? These are cheap units and are known to fail.

Thank you for your reply.
Just tried it with other power supplies. It won't boot up. LAN light is on.
I think the bootloader or the flash memory chip is damaged.
The voltages I found on the board are as follows:
1V, 1.25V, 1.65V, 3.3V, 5V, 19V.

Maybe someone has a NAND dump. I can flash the chip, I also have a new chip (if the original memory chip is dead/broken).

 

[Tech9]

The voltages I found on the board are as follows:

If you have a thermal camera you can find right away which one of the 7-8 step-down converters used is blown. This is the most common defect. RT-AC86U dies in a similar way with LAN4 port lit when one MT3125 inside decides to retire. You can feel it with your fingers as well - just place the PCB in the fridge for 30min to cool it down. You can often see it if you look carefully - the VRM are usually 3x3mm square tiny ICs. Don't remove the flash chip yet.