Is there any way to turn only one of for example 3 locomotives off? Also I want that the pantograph isn't up.
In the scenario editor, yes. In game, 50% yes. Here I'm assuming you know the basics of creating scenarios. Click on the loco you want to disable a couple times until a flyout on the top right appears. On that flyout there will be a checkbox to 'Broken locomotive' (Sorry I don't know the exact name by heart, you'll certainly find it) Rinse and repeat to all locos. In game, only specific DLC supports turning of locomotives. For instance, virtual railroads allow you to turn of individual locos/DVT-s. Most of the DLC from DTG though doesn't support this, or at least not to my knowledge. Please tell us what DLC you are using and if we need to undertake some cheesy moves to get your one loco you so desperately want turned off, off. Cheers, -ProfCreeptonius