Identifying Shielded Twisted Wires with Connectors

[DLINNI2000]

I have a harness with closed connectors (about 30 pins in each one of them),with about a dozen of twisted shielded wires.
need to mark them to know which one is which.
Tried to connect a needed pair to a ac power supply and find a wire with ac sensor, but on the low voltage shield blocks the signal, on a higher voltage sensor reacts on every wire.
Please help, is there determine to were every wire belongs to?
Thank you.

 

[Baluncore]

Welcome to PF.
So you don't have a multimeter.
Get a small low voltage flash light etc, then get a couple of wires, connect one to each side of the switch.
Those wires are your test leads. With the light switched off, touch the ends of the two wires, it will light.

Connect one test wire to one pin at one end of the cable.
Brush the other wire against the pins at the other end until you find any connection.
Record the connection, then move to the next pin, repeat.

The outer shells may be connected. Some pins may tie to more than one pin at the other end.

 

[tfr000]

Or just use a multimeter. Trying to do work like this without one is going to be difficult at best.