I got my first tmcc cab1 setup yesterday - (LOL about 27 years after it first was introduced) Both of my f3s would run but had no sound when I tested using ENG1 - the sound is in the B UNIT. It took me a day of messing around and reading post to realize that the only way to make the F3 Power Unit and the F3 B unit to work with sound was to program them both with individual cab IDS. When doing this you need to assign the power unit and the b unit and dummy all with the same engine number. So my 2240 A unit is engine 40, my 2240 b unit us engine 40 and the dummy 2240a is also engine 40.
I also have a 2368 F3 Postwar Celebration and followed the same as above giving it a engine number 68.
Also to keep in mind - you program each unit separately on the track.
Place the unit in program mode
Set back on the track
Turn the power on
Press eng and give it the number ##
Press setup and it will blink the headlights or make sound
Turn off power
Change the Unit from program to run
Turn power back on
Now it works - repeat for all units
I played around with the sound not working for many hours and did not realize you have to set all the pieces to the F3 to the same engine number or they don't work.
Hope this saves someone time.