There's an option to turn them on/off from the KORD YouControl Menu.
However, this will only control the extra apron lights, but you should always see some light, because basic lighting is included in the scenery in any case, so it will never be pitch black, the software controlled Dynamic lights are the additional lights that, if they weren't generated dynamically, would have killed the fps, so only the 7-8 closest to the terminal you are on will be lit. Those are the ones that can be controlled by the menu.