just tells you if you are passing signal, for exapmle you put one end of the multimeter tester in say pin one on the mini xlr and the other on the shield of the mini plug, you should get a signal, so follow the steps for each pin, so you should get a signal from the shield of the mini plug to pins 1,2,4 then on the tip of the miniplug to pin 3 and ring to pin 5,(thats assuming the same pinout) seeing that it works for the other mic not sure why it would be wired "wrong" though