I tried to connect Phoenix simulator to my Tx-Futaba 4EX. It was showing connected but not responding to stick movements.

I opened the case and saw that three of the connecting wires have lost connections. (Pic attached)

The wires are marked as A, B & C with corresponding probable connections as A, B & C.

The wire A seems to some kind of earthing connection. The three connections on board are -

A-GND2
B-OUT
C-VCC

I loosely connected them and could see the Tx work.

I am planning to solder these connections.

Am I moving in the right direction? Can someone help me confirm?

Does anybody has the circuit drawing of this Tx.

Did the soldering.....working now....