Taillight wasn't working, now circuit blows fuses constantly

I've got parking lights, no turn signals and no brake lights.

Ive been staring at Ford's wiring diagrams, and I hadn't had a chance to really tear the car down to look for the harness as it travels other than the trunk and under the dash.

It started when I had the car painted, just the one taillight would light up with the parking light, but wouln't change state when the brake was pressed or when turn signals were on, so missed ground or crimped wire, right? Now its gotten to the point where its blowing fuses and the vehicle has no operating brake or turn lights.

Even the center is out, which is a different harness/segment of that circuit altogether.

Worked on it today, found the orange/light blue burned in half on the chassis side of the taillight harness in the trunk about 3" from the fuel cutoff switch. Soldered it and thought I was done, now 4 fuses later I'm frusterated as all hell.

The fuse won't initially blow, I've shaken as much of the harness as I can find, the only thing I can potentially think of is that it happens after a period of time of more than 2-3 minutes, and possibly when starting the vehicle.

However, once I gave up, it hadn't blown after 30 minutes of molesting the pedal and multifunction switch in testing.

I'm as lost as ever, and I don't even know where to start. I thought about buying a new multifunction switch, and pulling the car's interior, removing all aftermarket wiring in the vehicle and taking it to a dealer. Yikes.

EDIT: The lights also seem dim, until you move the multifunction switch half left or right.

I don't see anything at the point the taillight mounts, the harnesses there or where the harness starts in the trunk, but has anyone run into anything like this and have an idea on where to look? I guess its a bad hot lead for the bright side of the bulb, but I don't know if there's a better way to check than just to find out which wire it is and work my way back to the front of the car.
 
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Chris, a little while back I replied to a similar thread on the Corral (or was it you? The part about molesting the brake pedal kinda' rings a bell). If it wasn't you, try comparing notes with the other guy.

If all grounds are good, I'd check voltage or even draw through the MF switch. The fact that the 3rd brakelight also acts up suggests one central issue I'm not seeing, or a couple of issues.

I'll double check that other thread later. I think it left off with a question about something someone else had posted (checking resistance or something), so I didn't reply.

Good luck.
 
I had very similar problem... I went nuts trying to fix it. I eventualy found that when I put in an adjustable clutch kit the new aluminum quadrant rubbed a tiny hole in the wire harness under the dash and kept shorting it out, I went through a ton of fuses!! Hope this helps you...