Good suggestions for tracing those elusive electrical problems.
Here's another. Connect a general purpose thermal breaker box in place of your fuse (available from your local auto parts store - about 5-10 amp capacity). When the circuit heats up again (it will because there's a short circuit somewhere), the breaker will open, then cool down again and close once the circuit is cool. While the breaker is opening and closing, wiggle the wire loom and see if you this makes a difference to isolate the short. There are also "tick" tracers, pen-shaped sensors that you pass along the length of a wire. The electromagnetic field the current produces causes the tick tracer to audibly or visually signal. If there's no current, there's no signal.
You can route new wire to bypass the bad stuff, but unless you follow the original loom and use the same color coded wire, this is bad news for troubleshooting years from now or for the next owner/technician. Have you ever tried to troubleshoot a PO's alarm system or audio system wiring? Usually so bad it's easier to start over.
Sherwood Lee
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