We investigated the possibility to find out the connections of an alternator, by checking the position of the sliders inside the so called "VW connectors" and it is possible.
As you will see in the COM connector below, the slider on the bottom is straight across the space in between the other two sliders on top. In this case, it is 100% sure that it is a COM connector. It doesn't matter if it has a 1 or a 2 pin connector.
When looking at figure 2 and 3 below, you will see that the sliders are in a different position than the COM connector above. Figure 2 shows the two sliders on the bottom. The one on the right is opposite of the one on top. Looking at figure 3, the sliders are exactly the opposite of the figure 2 connector.