Edit: Fixed by replacing the main board. I probably could have just added a BLTouch which was considered, but the USB port was unusable and I need that. I’m keeping the old board to mess around with it for later though. Possible good learning experience to be had.

I picked this up as an Amazon return/open box. The person that returned it just swapped their old printer and returned it.

Anyways, I was able to get it running and starting it up I am able to move all axis like normal. But when I select Auto Home the z will lift about 5mm. This lift happens no matter where it’s located. The head and print bed will move to their zero points and touch the sensors then both move to roughly their center points.

From this point all the axis will only move in the positive directions (starting at ~145 and can move to 150 but won’t move back to the 145 position. X, Y, and Z will all do this).

From what I found, it sounds like the BLTouch firmware may be installed, as there is also a leveling option in the menus. I’m not sure if this would explain the axis movement issues though.

I have tried reseating all connections, tightened power supply connections, resetting to factory through the menu and gcode, and changing/updating firmware.

Updating the firmware seems to be failing as it boots up normally and the versions don’t change (formatted to FAT32 with 4k sectors). I’m guessing I may need to replace some hardware but if there’s anything else I can try first, I would love to get some input.

Printer info: Ender 3 pro, software 2.0.8.27, hardware 4.2.2, 2.0.8.2 April 28 '22