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The push for legality, or wires out, wires in

March - April, 2006

Surveying the Scene

Tunebug cleaned

The first order of business once the Tunebug was safely home was to get it inspected and registered here in Utah. The car is old enough that emissions testing was not required, but it would have to pass a safety inspection. Having working lights and brakes is a good thing. So I went through the car trying to figure out what was broken that I'd have to fix right away.

  • Turn signals didn't work
  • Brake lights didn't work
  • Horn didn't honk
  • One low beam was out.

This didn't seem too bad, so I got to work trying to sort things out. After some poking about under the dash, I found a bad connection to the turn signal switch. A quick new connector and the turn signals were once again blinking. One down. I figured the headlamp bulb was just bad, so that was an easy part to get. Brake lights were a little more tricky, but I eventually chased that to the stop light switch, which is a pressure switch that screws directly into the brake line. Never seen anything like that, but it was added to the parts list.

Tunebug still had its original wiring harness, and it was in pretty good shape all things considered. It made me worry a bit, though, and I decided that rather than continue to chase electrical problems I would just replace the whole thing right from the get go. This would insure good wires and connections, and I would also be able to make sure that the car was wired up the correct way. The car is, as far as I can tell, still remarkably stock. A factory-style harness should wire up with no problems, and then I would know exactly what I had.

Parts in, wires out

Diving In

A phone call to the nice folks at British Wiring got a new harness and tools on the way. Some new light fixtures and gaskets came from Moss. While I was waiting for the new parts to come in, I decided to go about removing the old wiring. While an experienced person could probably do this entire job in an afternoon, I work slow when I don't know what I'm doing. I rarely seem to know what I'm doing!


Removing the old harness proved to be quite a bit of fun. A Bugeye doesn't have all that many wires and almost no interior trim to remove. It was my first chance to look deeply into the car, and for the most part I was pleased with what I saw. A few small rust spots, but nothing hugely unexpected. The Tunebug is a sound little car. Wires and lights came out over the weekend, and all was ready for the new bits.

Old harness
The entire harness, yup, that's it!

In With the New

Everything came out easily, and the poor little Tunebug was blind and stripped out. The new harness came in, and with one exception (more on that later) the new harness went in simply. I took lots of pictures when I removed the old harness, and made drawings for each component to mark how the connections when--where I could see the wire colors. I kept the old harness, but only needed to use one connection (one of the gauge lamps). The new harness fit right in, and wired up according to the diagram. The Tunebug is still essentially stock, so it made figuring out the connections very simple.

Bare Bug Wires go in

Once it was all back in, everything checked out and it all worked! Well, with one minor exception...

Standoff With the Switch

These early Sprites, along with other British cars from the era, used a pressure switch to activate the brake lights. The switch screws into the brake line and is activated by fluid pressure. At least it is supposed to be activated by pressure. No activation was to be had. After some encouragement from the folks on the British Car Forum I was able to get the old switch and the the 4-way union it was attached to out of the car and onto the bench. Unfortunately, I couldn't get the switch off of the union, though I tried PB Blaster, heat, big wrenches, and a hammer.

Recalcitrant switch

So the BCF to the rescue. Chris, a forum member, offered to send me a new 4-way union, as he was upgrading his Bugeye and didn't need it anymore. Wonderful folks there. It showed up a few days later, and I was able to get it installed and working up in a short time. It showed up as I was just about to leave for the day--instead I got the brake lights working and took the car down to be inspected and licensed. What a day, my first legal drive in the Tunebug!

Brakes leaked (fixed later with a new brake pipe) and a few other little things, but I was legal and driving around. My first project completed, and with a minimum of fuss and frustration. That will come later, I'm sure.

First legal drive

Final Thoughts

All in all, this proved to be one of the best things I could do for the Tunebug. I'm more confident now that the wiring is not one of the things I'll have many more issues with, and it gave me a chance to get a good close look at the car. A few final thoughts and tips from my experience:

  • Get the crimping tool if you get a harness from British Wiring. There are a few connections you'll need to make, and this makes things much easier. Get a good supply of bullet connectors as well--the folks at British Wiring will recommend what you need. Always nice to have a few extras.
  • On a Bugeye, the wiring diagram in the Haynes manual seems to be accurate. I used that as my reference, and everything seemed to line up easily.
  • The sub-harness for the headlight dip switch on a Bugeye doesn't come with a new grommet for where the wire goes through the firewall. That hole is 3/4". The main harness includes all the necessary grommets.
  • Keep your old harness! I wound up needing one light socket from the old harness, as the one from the new harness didn't quite fit.
  • Take lots of pictures and draw diagrams of all the switches. I did both, and the references were very handy. I couldn't always figure out the old wire colors, but I was able to make enough notes to make the reassembly fairly easy.