Help!! I have just assembled a ctc prusa i3 copy, thanks to some excellent youtube vids since the instructions are garbage. However the extruder motor is not working and despite hours and hours of research I cannot make it work. The motor works fine if you plug it into the x axis cable, but not on it’s own cable, and the voltage readings are radically different between the two cables when tested. the x asis motor, working perfectly gives the follwing readings when working: negative probe on meter on black wire, red and green fluctuate between 0 and just over 1 volt the blue wire fluctuates also between 0.2ish to 1.8v, However the wire to the extruder motor gives a much higher reading between the black and blue wires is 11.3v This doesn’t seem right, and I think it may be the cause of the problem, but I a newbie at this and do not know what to try next. If you have any info that could help me out, or links to any pages that have, I would be mega grateful!!

Ah, I think it is the stepper motor driver. If you swap it with another socket the problem travels with it. More on order (several, just in case)

Yes just about to say that. You did the same as me and went for the most challenging printer for your first one ?. Hope you get it fixed!