Recover Thingy91x if USB not responding.

RE: Recover Thingy91x if USB not responding.

NormisL4 — Fri, 06 Jun 2025 20:31:42 GMT

I was able to recover the device by following the guide here https://hello-nrfcloud.github.io/firmware/html/troubleshooting.html#factory-reset-bootloader

Completed the steps:
1.) Downloaded the zip https://github.com/hello-nrfcloud/firmware/releases/download/v2.0.1/connectivity-bridge-v2.0.1-thingy91x-nrf53-dfu.zip

2.) Moved Switch to nRF53

3.) Powered on device by holding button2

4.) Executed command `nrfutil device program --firmware connectivity-bridge-v2.0.1-thingy91x-nrf53-dfu.zip --traits mcuboot`

For those who might me struggling with the same problem in the future my nrfutil version:

nrfutil --version
nrfutil 8.0.0 (54d8087 2025-01-07)
commit-hash: 54d8087a38b73b6e56942fb1b024b62365f06731
commit-date: 2025-01-07
host: x86_64-pc-windows-msvc
build-timestamp: 2025-01-07T14:31:30.208979700Z
classification: nrf-external

I guess this ticket can be considered as solved.

RE: Recover Thingy91x if USB not responding.

NormisL4 — Fri, 06 Jun 2025 16:24:22 GMT

Thanks @dejans for replying.

Yes the device working before. I was applying apps from quick start and everything worked fine. I managed to send UDP message via cellular network by using AT commands.

Only thing is that device in https://hello.nrfcloud.com/ I received such message:
The fingerprint you have provided is not recognized, and we were unable to identify the device it belongs to.
This didn't bothered me much.

I build my own application in VS code by using nrf Connect SDK 2.8.0. The Board Target was set to thingy91x/nrf9151/ns

As *.bin files and *.hex files didn't worked for me (because of the mentioned 'Thingy91X requires a target when firmware is a hex or bin' Error), I applied dfu_application.zip through nrf Connect for Desktop v5.2.0 Programmer.

I tried to flash the mentioned thingy91x_hello.nrfcloud.com_v2.0.1.zip with these steps:

- Attach device via USB type-c to PC

- Power on device by holding button2 (This is the only method how device is responding)

- nrf Connect for Desktop v5.2.0 Programmer: Clear all files

- nrf Connect for Desktop v5.2.0 Programmer: Add file thingy91x_hello.nrfcloud.com_v2.0.1.zip

- Select "MCUboot" device And write on device.

The same Error is returned via this command via USB cable:

nrfutil device program --firmware thingy91x_hello.nrfcloud.com_v2.0.1.zip --serial-number 1E462C2EXXXXXXX --traits mcuboot --x-family nrf91 --core Application

RE: Recover Thingy91x if USB not responding.

dejans — Fri, 06 Jun 2025 12:37:12 GMT

Hi,

[quote user=""]It seems that I may have uploaded a non-working application to the Thingy91x. Therefore Device is not conectable via USB.[/quote]

Which application have you flashed to your Thingy91X device? Was Thingy91X working normally before flashing this unsuitable application?

[quote user=""]If I'm trying to flash it with the provided thingy91x_hello.nrfcloud.com_v2.0.1.zip package[/quote]

How did you try to flash it?

Best regards,
Dejan