Ctc shifting during prints can't figure it out

[ebam]

Printed black piece 1st with filament spool on side of the printer, pink/purple was next and was printed with the spool at the side of the printer near the bottom and then moved to above the printer, yellow was 3rd with spool above the printer for the whole print. When comparing the black print is near perfect for the layers that are where the purple and yellow have shifted, they’re also not in the same places. I have checked the belts, pulleys, made sure there is no tension on the filament. Due to the shifts being in different places it suggests it is not the z-rod being bent etc. Completely at a loss as to what else it could be. Any ideas anyone? Thank you

[Asuder]

Check all the wires to the steppers. I had this problem for quite some time, I ended up rewiring a stepper motor and the problem was solved.

Use a multi-meter and test the resistance in each wire.

cheers,