ORIGINAL: P-40K-5
even the cheapest of cheapest non-resistor plugs rarely fail. so what makes these any different?
What makes them different is obvious, they fail.
Even when they fail they will ohm check the same as a new one. You aren't the first to ask these questions or try to figure out the reason. Frankly, it's not worthspending much time onwhen the cure is only a couple of bucks.