Bricked debugger on nRF54L15-DK

RE: Bricked debugger on nRF54L15-DK

rba — Wed, 02 Apr 2025 19:09:54 GMT

Unfortunately I did not find a fix. I ended up getting a replacement nRF54L15-DK board. It arrived today and this one works as expected.

RE: Bricked debugger on nRF54L15-DK

helium3 — Tue, 01 Apr 2025 15:33:24 GMT

Im having this same issue, did you find a fix?

RE: Bricked debugger on nRF54L15-DK

rba — Sat, 29 Mar 2025 10:14:23 GMT

I have a similar issue. I just received my nRF54L15-DK v. 0.9.2 a couple of days ago. Yesterday, I managed to flash and get the blinky example to work. Today, I cannot reach the board anymore through VSCode.

What I've tried

- Measured VBUS: 5V, VDDIO 1.8V;

- A different USB-C cable. No change. The same USB-C cable can debug other boards;

- nrfjprog --recover: ERROR: No debuggers were discovered;

- I _can_ reflash the target nRF54L15 if I connect an external J-LINK debugger in the DEBUG IN/TRACE header, but the expected LED0 does not flash anymore;

- I _cannot_ use the built-in debugger to debug external targets via the DEBUG OUT header;

- I cannot find the board in the Board Configurator from nRF Desktop

In my case, the LD1 flashes irregularly for 1-2 seconds when I connect it to my macbook, but after that it remains off. The same happens if I connect it to a USB-C power brick. Once in a while it will flash briefly and stop again. I suspect the debugger is bricked, but I'm not sure why.

I didn't change anything from yesterday to today -- I did leave it plugged in overnight, but I'd be surprised if that's enough to damage it.

Are there any more steps I can do to try and recover it?

RE: Bricked debugger on nRF54L15-DK

PaKa — Wed, 05 Feb 2025 11:45:34 GMT

The green LED lit up on the picture shows the debugger is powered up and code is running, blinking pattern tells you what issue you may have so good tip is to report that as well if you see issues.

RE: Bricked debugger on nRF54L15-DK

Nick Stoughton — Tue, 04 Feb 2025 16:41:43 GMT

Aha! After leaving it switched off for 12 hours, nrfjprog --recover finally worked! Thanks! All is now working...

RE: Bricked debugger on nRF54L15-DK

Nick Stoughton — Tue, 04 Feb 2025 16:13:53 GMT

I have attempted both recover mechanisms, but it just says

- [Probe] Timed out waiting for response from worker. (Generic)

VBUS is 5.2v, VDDIO is 1.75v

RE: Bricked debugger on nRF54L15-DK

Priyanka — Tue, 04 Feb 2025 09:39:30 GMT

Hi Nick,

Unfortunately it's not possible to reflash the debugger. But it's also pretty difficult to brick it (As mentioned by Paal).

Could you try nrfjprog --recover or nrfutil device recover?

Also, could you share what error occurs when you try to flash? And also please share the pictures too.

Regards,

Priyanka

RE: Bricked debugger on nRF54L15-DK

PaKa — Tue, 04 Feb 2025 09:27:59 GMT

You are not able to program the debugger that way so that is not the issue here. Trying to reprogram that device will most likely brick your board permanently so don't try it! Check all power supplies voltages on the nRF54L15 (all decoupling caps) and post here with a picture of the board.

What version is this of the DK? Are any of the LEDs lit up?