The wire in the door may not be there, unless you already have the premium BCM.
I think pin three is the one you need, but my memory sucks.
BTW, when you connect a VTSS enabled BCM or PCM to a non-VTSS enabled PCM or BCM it will automatically enable VTSS, so keep in mind that you are stuck with it. Your PCM will always require a VTSS enabled BCM after connecting one to it.