I don't have a scanner so I'm afraid I'll have to do with my crappy cam.
As far the pins: like I said there are 2 sockets, and both have cables soldered to them (to the same pins), so I presume either the switch is to switch a combination of the pins, or to switch the pins off.
I don't know what the exact pin numbers are on a CIA, but seen from the top (=backside of the A2000), there are the following wires (all on the left of the socket):
white on pin #13, yellow on pin #15 (bottom socket)
green on pin #13, brown on pin #15 (top socket)
The bottom socket sits on the mobo, while the CIA sits in the top socket.
The wires are connected to a switch:
(the switches moves in direction between rows 123 and 456)
1|4
2|5
3|6
1-connected to 6
2-brown
3-yellow
4-connected to 3
5-white
6-green
I hope this makes it a bit clear.
