Moriarty -- if you're wondering how you can avoid nuisance electrical gremlins like this, it's pretty easy to do on an ERA (even one that apparently had a missing hi-amp connector). The wiring configuration of the fuse blocks makes running a voltage drop test really easy on most of the intermediate connections. Just turn your headlights on, put one lead of your VOM on the left screw of Fuse #1 and the other lead on Fuse #7 (High Beams) or Fuse #8 (Low Beams) and measure the voltage drop. Parking Lights are on Fuse #6 and Brake Lights are on Fuse #5. Before that brown wire finally gave up, Fuses 6, 7, and 8 would all have likely shown a hefty voltage drop of probably a volt or two. Gaz will tell you that a half volt or less is probably acceptable, I'd give it a little more. Just remember, you always perform a voltage drop test with the circuit loaded. The reason we didn't run a voltage drop test on your problem is that the circuit died when you hit the light switch. If turning the light switch on had just created "dim lights," then we would have performed the voltage drop test along the circuit to find the weak connection and it would have pointed right to that faulty connector.
