The floor in my departure elevator is black, here is a screenshot,
http://steamcommunity.com/profiles/76561197992185992/screenshots/

It is not a custom texture, it is one of the stock elevator instances. When i click edit instance, it is the exact same texture as the arrival elevator, which does show up

Let me search for that for you...

mapping-help/elevator-issues-t6396.html

mapping-help/departure-elevator-floor-t5664.html

mapping-help/lighting-in-elevators-t4292.html

mapping-help/elevator-lighting-and-doors-solved-t4239.html

mapping-help/elevator-lighting-error-t3980.html

mapping-help/bad-lighting-in-the-elevators-solved-how-to-inside-t3649.html

mapping-help/how-do-i-properly-light-around-an-elevator-t831.html

Lol, sorry iWork925, searching is not my strong point. Thanks for all the links.

Haggis, that is not a problem on the texture, but on the lighting. I think it is a light_spot set by default to "initially dark" that hasn't been set to active anytime. Or maybe the env_projectedtexture. Look for them and their outputs in the "departure_elevator_base" or in the "_logic" instances...