how do i trace the wires to the door switch on an automatic washer?

i bought the switch,the repair man came and didnt remember what he had taken off. i live in china please for gods sake someone help me.there are 3 wires 2 brown and a red with two wires in one.i need to know how to trace the wires live neutral and common please help.these are ging into the door lock on a front loading automatic washing machine thanks sooooo much