Step 12: Test Your Connections
There should now have 3 wires sticking out of the top of your microphone casing. If it hasn't been done already, strip about an inch of plastic off the ends of each of these wires.
Using the continuity tester on your multimeter (normally has a picture of a diode next to it) touch one probe to one of the pins on your XLR plug and then, one at a time, touch each wire at the other end. For each pin, there should only be on corresponding wire that gives a positive reading of being connected.
If more than one wire gives you a positive reading, you need to remove everything once more and check the connections.
Also, if you find a pin that does not seem to be connected to any wires, try turning the switch on. If that still doesn't work, you need to disassemble and re-check your work.
Speaking of the switch, be extra careful to make sure that the switch both turns on and off.