SD and USB reading issues
Hi everyone,
I’m having a persistent issue with my Prusa printer and I could really use some guidance.
The problems:
The printer recognizes when an SD card is inserted, but it cannot actually read the contents (always shows “No SD card”).
When I connect the printer to my laptop via USB, the computer does see the device, but slicer software (PrusaSlicer, Cura, etc.) cannot connect to it.
Steps I’ve taken so far:
Updated to the latest firmware.
Replaced the motherboard with a brand-new one.
Replaced the display module (where the SD card slot is).
Verified that both the new motherboard and display power on and appear functional.
Tried multiple SD cards, freshly formatted (FAT32).
Tried connecting with different USB cables and on different computers.
Current status:
Printer powers on normally.
Still shows “No SD card” even when one is inserted.
Laptop sees the Prusa over USB, but slicers can’t communicate with it.
At this point I’m not sure if I’m missing something obvious, or if this could be another hardware issue (cabling? board revision? something else).
Has anyone seen this combination of issues before? Any suggestions on what to test next would be super appreciated.
Thanks in advance!
RE:
I think the early printers had issues with any SD card over a certain size: presently it's 32G, but earlier not so sure it wasn't lower. Also, make sure the card only has one partition/volume. If you did partition a 64 or 128G card into multiple partitions, make sure the first partition is the FAT32, the printer won't see secondary partitions/volumes.
Since you replaced the SD slot when you replaced the control board, you probably aren't having the bent SD card slot issue. But might be worth checking. On the early control boards the metal frame of the SD slot can warp and it pulls the slot pins away from the SD card. The system knows there's a card but can't read it. A patch was a thin plastic strip between the reader and something --- it was obvious when you look at the mechanicals from underneath. I think I used a 1mm print. Others cut up credit cards.
And you might want to verify the ribbon cable is installed properly. It can be reversed or even plugged in offset a pin or two.