Reverse Lights

Quick post today. After not having operational reverse lights for pretty much the entire time I have owned Hapy, they are now operating.

Bus Reverse Lights - stock

reverse switch

Let's start with how these lights are supposed to work. On the transaxle, there is a small switch threaded into the case. It has a small pick-up inside the transaxle that is depressed when the reverse gear is selected. My original transmission had gummed up the switch, so it didn't work. Or, maybe it was just old and failed. It doesn't matter. While I could have replaced it, I was focused on other stuff... and then that engine swap thing happened... Anyway, that switch receives 12V from the positive side of the coil through a black wire. The wire, obviously, goes to one side of the switch, and the signal is sent from the other, down another black wire, to the driver side reverse light. These 2 wires are bundled together for about half of their travel, separating near the low-point of the spare-tire well. The source wire goes to the coil. The signal wire goes to the light, and a second wire, which is part of the rear wiring bundle, takes the light signal to the passenger side. So simple.

Bus Reverse Lights - after engine swap
Like I mentioned above, the original source of the 12V is the coil. If you are running an engine that had a coil, that works great. The TDI, of course, doesn't, so I have to find an alternative source. Fortunately, since the 12V source wire split off from the bundle at the low-point of the spare tire well, AND all of my electronics are in the spare tire well, this turned out to be quite simple. I located a switched source among the wire bundle and wired an in-line fuse into it. To the other end of the now-fused circuit, I connected the black wire from the reverse switch. I didn't mention before, but I installed a new reverse switch into the rebuilt transaxle when I installed it into Hapy.

Testing
To test, I put Hapy into reverse and turned the ignition to "run". The driver-side reverse light lit up. It was actually pretty bright. Nothing from the passenger side. Now, before immediately assuming something in the wiring was all jacked, I figured I'd look at the bulb first. 3 Phillips screws later, and... the passenger side didn't even have a bulb. Hahaha. I guess when I replaced the light fixtures all those years ago, I ran out of bulbs. Fortunately, I had a single-filament bulb, so with a quick twist, I tested again. This time, I had both bulbs light up.

At this point, I realized how fortunate I was and called it a day. Yes, I could have gotten into all kinds of other things, but it was already 4:PM, dark was approaching and I knew that when you have a win, take it and don't be greedy.

So, that's it for today.