A ver si esto que acabo de encontrar te sirve de algo.

Pinouts for Virtua Fighter 3 - Sega Model 3 step 1.0 PCB set.


POWER CONNECTORS
----------------

JST CN13
1-8 - +3.3 volts
9-18 - Ground
19-24 - +5 volts

JST CN14
1-5 - +5 volts
6-10 - Ground

JST CN15 (Used for cage fans only)
1 - +12v
2 - NC
3 - Ground


VIDEO
-----

JST CN6 (Can also use 15 pin VGA connector CNVGA1 but output at
24KHz/H;60Hz/V)
1 - Red
2 - Green
3 - Blue
4 - Composite Sync
5 - Ground
6 - NC


AUDIO
-----

JST CN8
1 - Left Ground
2 - Left Signal
3 - Right Ground
4 - Right Signal


CONTROL INPUTS
--------------

JST CN2
1 - Coin 1
2 - Coin 2
3 - Test
4 - Service
5 - NC
6 - NC
7 - Start P1
8 - Start P2
9 - Up P1
10 - Down P1
11 - Left P1
12 - Right P1
13 - Button 1 P1
14 - Button 2 P1
15 - Button 3 P1
16 - Button 4 P1
17 - Up P2
18 - Down P2
19 - Left P2
20 - Right P2
21 - Button 1 P2
22 - Button 2 P2
23 - Button 3 P2
24 - Button 4 P2
25 - NC
*Please confirm the UDLR pins with the test menu, as these are from
memory!


CONTROL OUTPUTS
---------------

JST CN3
1 - Coin Meter 1
2 - Coin Meter 2
3-8 - NC