I have a problem with my Ender 3 V3 SE: the Y-axis is making a weird noise when it moves weirdly, but I can’t find what’s causing it. First, I tried lubricating it, but that didn’t work. Then I disassembled the rails and checked for possible scratches, but that wasn’t the case either, and the internal bearings don’t seem to be affected. The motor and the tensioner bearing don’t make any noise or have any weird friction either.
Disconnect the Y motor cable first. Move the bed slowly by hand. Listen for noise at different positions. Rotate each Y rod and test again. Check the belt tension carefully as well.