This one was pretty easy. Four wires, nothing tricky, 20 minutes.
Exterior of KANI24-500
The KANI24-500 is the baggage car used on Hokutosei sleeper express trains. This model is part of my Tomix Yumekukan set. It has a set of markerlights and a signboard that light up when the car is at the rear of the train—which is 50% of the time. The other 50% of the time, when the car is at the front of the train, these lights are all off. One light, one function, easy-peasy.
The car in pieces
Taking the car apart is straightforward. The shell pops off in the usual way. Make sure you don’t lose the red lightpipe, though: It loves to fall out when you aren’t looking. The trucks are secured with a Phillips-head screw each. Remove the truck nearest the markerlights, and the lighting assembly pretty much just falls apart from there. There is a black plastic cover, a brass…something, and the lightboard itself.
The intact lightboard
The lightboard is secured to the pickups with only a little tension. Electrical contact is made with two brass pickups that need to be desoldered and removed. A solder wick or desoldering iron is essential. The pickups sit in a recess on the top of the board (under all that solder), and come out easily. The board itself is quite large for having basically just three SMD components. This makes working with the board very easy. Good for us.
TCS FL4 decoder
I selected a TCS FL4 for this install. While this 4-function decoder is rather overkill for the project, it’s considerably smaller than its 2-function cousin the FL2. I kept the green function lead, cutting off the remainder, and the black-and-white ground lead. Don’t confuse it for the black lead!
Decoder soldered to pickup rails
The steel rails inside the bottom of the shell do not come out, rattle as they might. I picked a point to solder where the plastic didn’t touch the rails, to avoid unnecessary melting. These things suck away heat like you wouldn’t believe, so be careful you don’t overheat the whole mess trying to get the solder to adhere.
Decoder soldered to lightboard
The lightboard is mercifully labeled, so there’s no need to guess which wire goes where. In this photo, I’ve already removed the two small brass pickups. The blue common is to the top of the photo, and the green function lead is to the bottom bottom. I just soldered these where the brass pickups used to be. There’s nothing on the other side of this board that needs isolation from the steel rails, so we’re basically done!
The decoder installed
I didn’t really bother measuring where I cut the leads. There’s plenty of room (and surprisingly, none of this is visible in the finished model!), so you can simply tape things down where ever you want.
Replace the brass cover thingy, making sure that it is squeezed in tight into the frame—it doesn’t just sit on top. Then screw the truck back on, which secures the cover over the lightboard. Pop the shell on—watch that lightpipe, again—and that’s it! We’re done.
Behold; light!
Besides setting the address, there’s really nothing to program. Make sure that CV51 is set to either 0d or 16d (depending on your convention for “forward” and “reverse”).