connector - Audio Jack Schematic

We are using this audio jack in our design. I am having trouble understand the schematic of this audio jack. My understanding is that

1. Pin 5 and Pin 4 : Audio left and right


2. Pin 2 or Pin 3 : Ground or Mic


3. Pin 1: detect

Can anyone confirm my understanding? I think that the switch is normally open and pin 3 will short with pin 1 when the jack is inserted.