Well I have slight problem with my truck blowing the fuse for my turn signals. I noticed none of my signals were working, so I starting pulling fuses until I found a blown one. It was a 15 (not sure if that is the correct size but that's what I replaced it with). The signals worked fine after that but not for long. After a bit playing around with it I found that the fuse blows when I put the truck into reverse. I would replace it and all four signals would work just fine, then I put it in reverse and it blows every time. A couple of years ago I replaced the bulb assembly on the drivers side back up light. I thought that it may have just gotten worn and weathered where I spliced it. I cut, stripped and re-spliced the wires and even replaced the bulb just for laughs. And it still blows when I put it in reverse. I tried following the wires under the truck but I have no idea where it may be shorting out. If anyone has any ideas I would appreciate it.

 

Is it column shift? I had a similar-ish issue years ago but it was when I put the ignition steering lock on. Turned out it was chaffed wire insulation in the steering column. Just a thought.

 

You wont belive this but I have the same problem with my 83 F100. Just found out last night it blows when put in reverse. I wont be able to look at mine till Friday or Saturday. But The switch for reverse is on the transmission shift linkage, along with the netural safty switch. Mine was just replaced last week. I will start looking in that area. If you come up with anything I would appreciate letting me know what you find on yours.

 

Mine is a manual 4 speed with the granny gear. I won't be able to do to much more exploring under my truck until tomarrow afternoon but if I find the culprit I will be sure to let you know.

 

Sounds like the reverse switch it shorting to ground, you signal lights an reverse lights are probably on the same circuit. I'd unplug the reverse switch and jumper the connector, if the fuse still blows it's likely at the lamp assembley, if not, it's the switch.

 

Well I bought a bunch of fuses and started looking. My problem was easy, found some bare spots on wires just before tail lights. From a old trailer light install I think. Was able to tape the bare spots and I am up and running. Just before this I was installing a reciever hitch, I think i must have moved the wires. Always check what you were working on just before problem pops up. In my case not very easy cause it seems like I am working on everything lately. Hope you have luck finding your probem.