Hi
One thing I know: with a CS2 or CS3 it is possible on a Märklin decoder to assign / re-assign functionality (a physical function (pantograph, smoke, etc.) or a sound can be activated by a different function (F0, to F 32) such as cabin lights, to dim them and to assign direction (Both, Fwr, Reverse).
With an MS2 I don't know
Cheers
Jean

I understand your question perfectly. My answer: sorry I don't know with an MS2 but it works fine with a CS2 or CS3 on an MFX Märklin decoder (less than 2 to 3 years old).
It may well be that this configuration capability is not on the MS2 Sorry. You may have to try at a friend's with a CS2 or CS3
On a PIKO train I am not sure you can.
Cheers
Jean

Some of those cab control cars have a mechnichal switch that changes the lights depending on the actual direction of travel. But it seems like this one has a function decoder. On a Mobile Station the easiest solution seems to be changing that decoder’s address to the same as the loco.

Hi
Here is the procedure on a CS2 (Release 4.2.9 (0)
1- CS2 with, loco on the programming track, power ON
2- Select the Loco decoder you want to change, select the wrench when in home position like this

3- When on loco configuration screen push the CV key

4- After the warning screen is displayed

and after it is acknowledged the following is displayed after a while

5- Press one of the function keys (on the right and wait until you get a screen like this

6- press the desired function on left top part of screen
It must drive also a physical function

7-push the wrench on a physical function and on next screen (middle) select when the function is activated : both directions, forward only, reverse only
8- validate to exit
9- store on the loco (arrow downwards to track) and validate
10- validate again
I hope this helps
Note: the screens you get maybe different depending on selected language and decoder type but this is the general idea.
On a physical output you also may decide if it blinks, flashes, glows like a fire and there is a dimmer
Cheers
Jean