71 super beetle defrost box

can anyone explain the wiring for 71 super beetle front defrost fan ? it has 3 wires two can be matched up with plug in, one is free and is beige or faded yellow and when you apply voltage to it the blower runs also there does not appear to be any power to the inside switch on the dash this wire that runs the blower has a spade connector on the end an i do not see a female plug for it.