Wegberg V8 – Problems with auxiliary transmission on ladder truck (DLK)

[Gion222]

Hello everyone,

I'm playing with the Wegberg V8 mod from Emergency 4 and I have a specific problem with the ladder truck (DLK).
When I try to return it to the barracks or move it, the game prevents me from withdrawing it and I think the reason is related to the auxiliary transmission (Nebenantrieb).

I can't find how to turn off this auxiliary transmission Nebenantrieb

What I have already tried:
I stopped the vehicle.

I checked that there were no other active commands.

I watched some videos on YouTube but they do not explain this part well.

Can someone please explain to me exactly how to activate/deactivate the auxiliary transmission on the ladder truck in the Wegberg V8?
Many thanks in advance.