Unresponsive 1XD Expansion

cactode

I'm in the process of putting together a new 3D printer and decided to use ClearPath servomotors for the main muscle. I have two Duet 1XD expansion boards (one for each motor) and a toolboard connected to a Duet 3 Mini 5+ Wifi, but I've run into a strange problem:

One of the 1XD expansions works perfectly; I can connect to it, change the CAN address, configure / command it, and move a motor around without any issues. The toolboard is the same way. The other 1XD, however, refuses to connect to the CAN bus. When it's turned on, the LED flashes quickly (but at a different / slower rate than the functional 1XD when it's trying to connect to CAN). There's no pauses, so it doesn't seem to be an error code. If I connect it to the CAN bus, it will carry on flashing at the same rate but will occasionally also flicker / skip a beat. The mainboard never recognizes that anything is connected on CAN.

I've tried a few things to fix this to no avail:

Changing the cables: The wiring harness that worked for the functional toolboard doesn't work for the broken one. Changing out those cables (just in case?) also didn't help.
Removing cables: Even with only power and CAN, nothing changes.
Checking the CAN termination headers: Everything is good there. Adding / removing them doesn't change anything.
Resetting the CAN: Adding the CAN reset jumper and turning the board on / off doesn't work.
Updating the Duet mainboard to the latest version: No effect.
Updating the 1XD firmware: No effect, especially since the toolboard isn't visible on CAN regardless. Doing this while the 1XD is in CAN reset mode makes no difference.

I'm starting to think that the board itself is a dud. Supporting this conclusion: the crystal on the broken board looks a bit toasted. It doesn't show up as hot when I look at it through a FLIR, but my oscilloscope is showing that the crystal isn't outputting any signals (the functional 1XD board shows a perfect 25MHz). I've attached a side-by-side of the dead / functional board (dead one on the left, working on the right).

My camera isn't great, but it hopefully captures the extra-dark looking crystal.

Any thoughts?

dc42

@cactode I agree with your diagnosis that something is wrong with the clock on the non-working board, and I am happy to approve a warranty replacement. Please email warranty@duet3d.co, and include a link to tis thread in the email. You will receive a response with a form to fill in.

Please accept my apologies for the inconvenience this has caused you.

cactode

@dc42 Thanks, I'll send an email over to them!