wired controller

Hi guys

Probably another stupid question from me again.

I'm an air conditioning engineer and I'm working on a unit that has a wired
Controller being fed by a 2 core comms cable. I don't know what transmission protocol it uses.
So the questions are how would it find out?
2 could use hook a xbee to transmit from the cable(for the controller) to another xbee with the controller connected thus making the controller wireless
Thanks guys

First of all, you should try to find some manuals, and not to just connect things to it.
For example if the comm is RS232 you would've fried your xbee's if you just connected them...

Hi its not rs232 signals it looks like differential signals and I've been thinking
It won't be able to be transmitted