Y-Axis length calibration/belt test error
I've been having a really hard time trying to get my i3 MK3s calibrated. I assembled myself and it worked fine out of the gate. I got a few flawless prints in and then suddenly a print failed, I tried to recalibrate and now I get y-axis length error every time.
I think the y-axis is moving okay. In settings I'm able to move it its entire range and even the XYZ calibration seems to work until it gets to the third point. It looks like it's found it (it hovers around the 3rd point for a while) but instead fails.
I've attached a video below of what happens when I try the belt test. I've tried tightening/loosening the belt, ensuring that the bolt on the motor is tight, adding lubricant to the y-axis shafts, and loosening the U-Bolts on the shafts. Same result every time. Any ideas on what I can try next?
RE: Y-Axis length calibration/belt test error
May sound stupid, but is there enough room at the back of the printer? Could the heat bed cable be hitting the wall and giving false readings?
Also if the belt is tight enough, is the grub screw in the pulley wheel tight?