How do you turn TCAS on?

First in the EFIS HSI range switch is a button in the center of that switch, when you press, the EHSI (lower center display) will show "TFC" in the bottom left corner.  Then in transponder, switch TCAS to auto or on, and switch the transponder to at least the "TA ONLY" position.  This should work for you.

Thanks it worked!

Its good stuff for sure.

Yesterday around 18:00 GMT on the "Long Hops" server at UGT, we had a final hop for "Jolly 54", where we got about 10 pilots together in 737's (well I cheated, I was in my 757 cuz I can't stand default 737s) and I had TCAS on.  We fly a pretty tight formation when we do this honorary flight, it's a big deal when someone has finished an entire hoplist on our server.  Most of the flight, it was screaming "TRAFFIC! TRAFFIC!" :)  I didn't want to turn it off, because it's nice to see where everyone is that I can't see thru the windows.