You can add Kato's LED light kit. Costs about $8 per car, cheaper in a 6-pack. In other words, it's lighting ready.
Yup. Kato sells drop-in lighting kits for all of their passenger car body styles. The contacts also serve as bearings on Kato passenger trucks; the contact point is the tip of the axle. They roll better than metal-to-plastic or plastic-to-plastic trucks do, so you win even if you don't care one way or the other about lighting.
Note on those light kits, they look very unrealistic and are finicky to install. I have a set of 6 installed and intend to modify the light dispersion bar they use. If that doesn't work remove them and eventually run real lighting, tediously installed small LED at passenger seats. The Kato lighting is a bright glow from one end and clashes with the excellent car details and at least for me it was 'kind of cool' at first and quickly became 'that looks wrong, totally wrong'. I am not a rivet counter at all, but counting bright glowing things is a little more obvious, and one huge light versus windows lit by small reading lamps at night... I have ridden Amtrak, there is no air raid spotlight at one end of the car during night time hours.
I agree with Ken. The lights are VERY bright. Three coats of paint on the interior walls and the light still bleeds through. They also flicker at every turn-out, diamond, and rail joint. Makes my BN passenger train look like a rolling disco !!! Guess that's fitting, since I model the '70s. I could hire The Beegees to play in the club car !!!
Thanks for all the replies. I have a hodge podge of different cars, and none are lit. So even if the Kato lighting kit was good, it would look out of place. @Run8Racing: Disco is not dead!
I'm gonna' try the "Easy-Peasy" system on my next lighting project. Doesn't use track power, it uses watch batteries. Can be turned on and off using a magnetic wand. As far as disco is concerned, unfortunately you're right. But...look up Steve Dahl at Comiskey Park in Chicago. We thought we had disco beat that day !!!
I remember a car lighting system that was a full length board with batteries. A plastic wand with a magnet at one end was used to activate the car lights on and off. Advantage was constant light with no flickering and not as intense. Disadvantage was in having to disassemble the car to replace the small batteries and the cost of those batteries. I do remember that the costs of those light boards was about the same as Kato's track powered boards but not who made them.
Intermountain used battery-with-magnetic-switch lighting on some of their Centralia line. The batteries were so hard to get at (and extract- I ended up having to pry them out through the car-end window with a jeweler's screwdriver) without damaging the cars that I ended up just leaving them out when I reassembled the cars. That, and IM shipped the cars with the batteries already installed... and they'd been sitting on the dealer's shelf (or the distributor's) for long enough that the batteries had leaked and corroded. Not fun to deal with. With significant re-engineering (a roof held on by magnets instead of snap-in tabs, perhaps?) it would be a decent enough idea, but as implemented it was more trouble than it was worth.