Extruder Trouble

Hi All,

Been printing merrily for a fair few months now, but have hit a snag.

All of a sudden the extruder motor on my Prusa (Ramps 1.4, Marlin, Mac OSX Lion) just clicks and jitters without actually turning. I've made sure the physical electronics are fine and tried turning it without any filament to make sure there isn't a jam. Also tried swapping round drivers, but the problem is repeatable.

Any suggestions as to what the problem might be?

Thanks!

Filter might be broken

filter?

replace your wires that go to the motor. one of them could be bad.

or

you could have a bad motor. if it had been over current for some time one of the the copper winding could have heated to burn thru the insulted coating. the fastest way to verify is to swap motors, a more methodical test is to take a+,a- and b+,b- and measure the resistance between windings.