Extruder Stepper Not Working

Hey All,

I recently replaced my extruder head and it required a change in the extruder motor direction. So I swapped the wires for the stepper motor to change the polarity of a coil and now the extruder just jitters instead of working.

If I plug the extruder motor into the x-axis and jog it, it runs fine. Now I know that swapping wires on the stepper motors isn't supposed to be able to damage the board, but I think that in this case it has. Any ideas about how to work out what's blown? Is it the stepper driver?

Also note: the heatbed now powers on when I switch on the power supply and won't respond to temperature controls. Not sure if this is related but it was fine before I tried to reverse the stepper direction.

I would work out the heated bed issue first. It's probably either shorted to ground or you have blown the FET that controls it.

If the extruder motor runs fine on the X axis driver then it's not the motor or the wiring. It's either a blown extruder driver or a wrong current setting on the driver. A DVM will tell you quickly where the current is set on the two drivers. If they are plugins you can move them to see if the problem follows the chip. If they are plug in's there's a sight chance that it's a bad solder joint on the board they plug into.