You can download a 2006 service manual from
http://aie-services-2.net/Sprinter/
Section 8w-61 covers the door lock circuitry, and specifically page 8w-61-2 shows the console switch (which has 6 wires).
(it has 6 because it has the two little independently-lit red triangles (that's two), the general "dash illumination" light (that's another),
the two signals from the top (one) and bottom (another) switch contacts, and then (in that
particular switch's case) a "common ground" that also serves as what the "moving contact" (which touches the top and bottom contact) is connected to. (the 6th wire: ground).
In a more typical (no separate triangles) "double throw" switch, the 5 wires are:
1: the moving contact
2: the top contact
3: the bottom contact
4: the (dimmable) power for the general dashboard illumination lamp (LED, actually)
5: ground for the lamp.
--dick