not so easy if i cant see the unit and test where wire are suppose to go but maybe a few tips will help.on a 3 prong normally the outside 2 are for the motor,one off them must have direct power in for one side of motor plus power for the light.one life wire coming in from mains can run thru on/off switch or you can use this switch for light only.this means life wire going thru switch to motor life and other is neutral.middle prong is the "switch"that trigger by foot control.sort the motor wires first and the rest will follow by logic.be sistematic and draw the circuit on paper,it also help to prevent confusion.hope the tip help
johan
March 2012
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix sewing machines.