Quote Originally Posted by the evil twin View Post
Think back a few weeks... did the fuse start to blow before or after you had the lights apart?
It might be a good place to check again.

Probably as much as 90% of electrical faults are caused by us humans touching things that weren't broke

The idea of the globe is to limit current.
If you use a small wattage globe like an interior light, a test light like in the screwdriver style probe or an LED in place of the fuse it means that only milliamps flow in the circuit so nothing gets fried or melts.
Very handy trick when you get bad power shorts to earth, switch mode power supply faults etc
You can power the circuit up and actually chase voltages to find the short rather than just picking things out of your butt to disconnect and blowing a gazillion fuses
The problem started after doing some sand driving through dunes and on beaches, plenty of corrugation and some heavy bumps which would be just the thing to make some badly positioned wiring rub through.
Don't know why I didn't think to use a light in place of the fuse as it makes sense and I am a Technician myself.