How to debrick Asus RT-AX59U

Installing and Using OpenWrt
1

Hello,

I built the 25.12.3 firmware with some extra packages (on the openwrt-website), flashed it to the router and after a reboot the router doesn't work anymore. It seems bricked.

Here is what is happening:

  1. Booting up the device without pressing any button, the led flashes once and stays green without any further blinking.

From pinging the device I can see that at some point during startup it sends between 2 and 4 pings and stays silent after:

From 192.168.1.10 icmp_seq=6291 Destination Host Unreachable
64 bytes from 192.168.1.1: icmp_seq=6292 ttl=64 time=1024 ms
64 bytes from 192.168.1.1: icmp_seq=6293 ttl=64 time=0.713 ms
64 bytes from 192.168.1.1: icmp_seq=6294 ttl=64 time=0.488 ms
From 192.168.1.10 icmp_seq=6295 Destination Host Unreachable

Pings get lost then. tcpdump shows no output.

  1. Booting up the device while keeping the wps button pressed permanently, the led is quickly flashing red (like 10 times per second). No ping gets through. If I release the wps button, the red flashing stops and the permanent green led comes back, flashes once, and that's it. Nothing else.

tcpdump shows no output, pings get lost.

  1. Booting up the device while keeping the reset button pressed, the led is flashing red slowly (like 2-4 times per second) and stays in that flashing state if I release the button. Pings keep working then indefinitely. However, I cannot ssh into the machine. The ssh client just waits for connection forever. Pressing the wps button or the reset button again in this state doesn't do anything.

tcpdump shows no output.

  1. Booting up the device and pressing the reset button once after around 4-5 seconds tcpdump -Ani eth0 port 4919 and udp shows:

09:40:22.853024 IP 192.168.1.1.46725 > 192.168.1.255.4919: UDP, length 1001
E.....@.@..............7.. y..Please press button now to enter failsafe...

Pressing the wps button quickly then doesn't do anything. Pressing the reset button again doesn't do anything.

  1. Booting up the device and pressing the wps button once after around 4-5 seconds gives the same result like 4). It doesn't seem to put me in failsafe mode either.

  2. Booting up the device and pressing either button after 1-10 seconds to catch the failsafe mode window doesn't work either.

What am I missing here, any specific procedure to get to failsafe mode or is this device beyond debricking with failsafe mode?

2

if it fails, Asus restoration tool from their home page.

3

@frollic Thanks. Tried that. Asus tool fails. It uploads the firmware to 100% but then cannot proceed. I get this status: Failed to recover the system.

Any other idea?

4

The OpenWRT reset/recovery should work, if it doesn't, serial.

5

Ok, guess it's serial then. Could you point me to more information for entering the router model via serial?

6

Disassembly is described at https://openwrt.org/toh/asus/rt-ax59u#opening_the_case.

UART pinout is printed on the PCB.

7

Lan1/Port1 is the only one active during failsafe. Connect to lan1 with correct IP, press reset button once during boot, and you will be able to reach device.

If that doesn't work, use Asus Recovery windows software flash order:

  1. ubi_cleaner for ax59u from remittor google drive here: Asus TUF AX4200 support - #241 by remittor
  2. reboot
  3. Flash asus 59u oem TRX
  4. reboot and done
8

That is fantastic, thank you very much @cookiemonster for taking the time to helping me out.

UBI was messed up, so the ubi_cleaner file you were pointing to fixed the router.

Thanks!