Unable to read SD cards  

RE: Unable to read SD cards

Posted by: @nick-i3mk3s

I know, my question was rather, how does changing the firmware help with diagnosing the problem? If printing via USB works, then that leads me to conclude that the firmware currently running on the printer is not corrupt, so what would be the advantage of changing it?

 just a suggestion as it's easy to do and little bits can get corrupt but forget my suggestion if you don't want it 

RE:

With no other suggestions, I've gone ahead and replaced the physical SD card holder on the PCB. Unfortunately, the same problem persists after replacing the SD card holder, so the holder doesn't seem to be the problem after all. I'm posting the procedure to replace the SD card holder here, in case it can help others.

The replacement part number is 693063010911  from Würth Elektronik. It's available from Digikey for about €3: https://www.digikey.co.uk/en/products/detail/w%C3%BCrth-elektronik/693063010911/3124581

To original SD card holder is made of plastic with a metal cover, and melts quite easily without damaging the PCB. To remove it easily, assuming you don't want to recycle it, I recommend using hot air reflow to heat the cover and pry it off with tweezers once the plastic is soft, then continue heating the exposed plastic which quickly melts. Use tweezers to pick the remaining bits of plastic off the PCB. It should come off very cleanly.

Use flux and copper braid to wick the remaining solder off the pads, then clean with acetone.

Place the new SD card holder on the PCB, it has two alignment pins that snap into the holes. Then use a solder iron with fine tip to solder the 4 mechanical contacts on the sides to their respective pads. Once it's soldered in place, continue with the data pins. If the pins closest together bridge, use additional flux and a fine tip solder iron to 'pull' out the solder bridges.

Clean any remaining flux residues from the PCB with acetone. Done!

Important: the SD card holders are extremely sensitive to heat, so I do not recommend reflow soldering with a reflow station to mount them. Since you can't use a reflow oven due to the LCD display being permanently attached to the PCB, hand soldering is the only way to mount new SD card holders.

RE: Unable to read SD cards

I've just upgraded the firmware of the printer to version 3.13.2, and that also didn't make a difference. So it appears that the problem is caused neither by firmware nor the SD card holder itself.

Any other ideas?

RE: Unable to read SD cards

Posted by: @nick-i3mk3s

I've just upgraded the firmware of the printer to version 3.13.2, and that also didn't make a difference. So it appears that the problem is caused neither by firmware nor the SD card holder itself.

Any other ideas?

2 ribbon cables, lcd pcb or the port on the einsy I'd take a guess at it being the lcd pcb you can get cheap clone off alixpress try swap the 2 ribbon cables round first though

RE: Unable to read SD cards

Already tried swapping the ribbon cables around, and didn't make a difference so going to guess it's not the cables.

Do you have a link for the AliExpress clone?

RE: Unable to read SD cards

I updated to 3.13.2 and now my sd card is not reading either. I tried to reflash to another version and gets half way through and fails no mater what i do . Barry

RE: Unable to read SD cards

Posted by: @nick-i3mk3s

Already tried swapping the ribbon cables around, and didn't make a difference so going to guess it's not the cables.

Do you have a link for the AliExpress clone?

Thought I already posted a link but isint showing here's one I'd say to get https://www.aliexpress.com/item/1005006070573638.html?spm=a2g0n.productlist.0.0.3e566d2200jQy0&browser_id=63c2b56d05484c8c8cd95bf8d8ecf9d2&aff_platform=msite&m_page_id=esfhdwacwcaxzcoq18b8f153d7a2087968e5b32d77&gclid=&pdp_npi=4%40dis%21NZD%2130.07%2128.56%21%21%2117.36%21%21%40210318c316989126157843515ee667%2112000035592412769%21sea%21NZ%212815522674%21&algo_pvid=36c5f13e-8345-4f73-aa15-44485bc9365c

RE: Unable to read SD cards

Posted by: @barry-jindra

I updated to 3.13.2 and now my sd card is not reading either. I tried to reflash to another version and gets half way through and fails no mater what i do . Barry

Maybeopen new thread about firmware not uploading what does it say when it fails 

RE: Unable to read SD cards

Unfortunately software (incl. firmware) updates are more often than not a bad idea, based on my own experiences. I would strongly advise not to upgrade any software or firmware unless there is a proven problem with the existing software/firmware that an update is likely to fix.

Meanwhile I swapped SD cards and display module with those of another Prusa MK3S, and that confirms the problem is in the display module. Not sure what the issue could be however, since the SD card holder itself is already replaced. I will proceed to replace the 74HC4050 level shifter chip, which is the only component left on the PCB that could be the source of the problem.

RE: Unable to read SD cards

Update: I replaced the 74HC4050 level shifter chip on the board, but even that doesn't fix the problem. What causes this issue is a mystery to me.

I've ordered the AliExpress replacement board, so fingers crossed.