Good question, couldn't find it either. Also not the main cabin lights. Just the desk lights. Weird! But I noticed the passenger lights seem to "magically" switch on inside tunnels???
I too have looked for it and haven't found it yet, but the passenger lights seem to be turning on automatically when going in tunnels. Maybe there isn't a button for them and they're just automatic?
For me, all interior lights only work inside tunnels (or similarly dark spaces). We’re talking cab lights, instrument lights, passenger lights… simply everything. Possibly something got messed up with the new lighting system?
I am quite certain that they said on stream that the passenger lights had to be switched on in each coach individually - a bit tedious, but I don't have TSW3 so someone may want to see if I am correct or not.
The passenger lights are always on, but in bright daylight, you can't see it because the sun is so much brighter. To turn on the cab light, pull the cab light switch toward you (Shift+H).
You don't need to switch on any passenger light. It is on by default as soon as the ZS (train line) is powered. The lights are always on. Fact is, at the moment, that you can't barely see them in daylight conditions. Basically all light emission gets blown away by the daylight yet. Generally that is a intended physical behaviour of light but it might be a bit to much yet. I'm sure the team is investigating that stuff already.
Also, even within the tunnels, I'm missing the lights on the dividers between the luggage racks, which should be quite visible.
But they are there. Each wagon got about 30 light sources to lit them up. Already to much from a performance perspective. But as you see, too less for good lightning of those ICE wagons. It's a compromise at at least we have to do.
