possible heater element, or main motor fault,
isolate the power supply to machine
now
isolate the wiring to each one, then pick one and reconnect it, turn back on the power supply and see if fuse is O K or blows. Which ever one blows the fuse/breaker is your FAULTY ONE that needs changing/replacing,
The motor fault MAY just be lots of carbon dust that is tracking to earth.
wirecutterman, March 2009