TMCC 2 Wire Base Cable Pinout

Would/could somebody please confirm which  2 pins on the DB9 connector that the red and green wire go to on the 2 wire TMCC Base cable that goes to the various TMCC accessory controllers. I read online that the red wire goes to pin 2 and the green wire goes to pin 5. I would just like some confirmation before I fry something. In standard DB connectors pin 5 is sig ground so that makes sense but pin 2 is receive data on the 9 pin d sub. It seems to me that we would use TX Data, not RX Data.

Thanks in advance!
Ken