Electrical woes, short in right rear turn signal

[HicksNthaStix]

Guys im about to pull my hair out, or what's left of it anyway. I knew this truck was going to need some work here and there, but these are the kind of things that make me regret taking it on.

Go to use my truck to tow for the first time since I got it. Go hook up my trailer and plug in my 7 wire, only to realize that the housing for the plug is there on the truck, but there is nothing in it. No big deal, I'll just wire one in. So a crawl up under it and get to work. HOLY CRAP! Well, the good news is that after I remove all of the unnecessary wiring under there, I should have enough scrap copper to pay for the entire truck. Parts of 3 different trailer wiring harness down there, none complete. About $1000 worth of butt connectors and hardly more than 6" of wire without one, and that's where they didn't just tape the wires together. Oh yeah, and about 3 miles of electrical tape. Anyway, I got that mess sorted out and cleaned up nice.

However, apparently there is a short somewhere in the right rear turn signal. I have traced it back to where it comes into the cab and disappears in the dash going to the fuse panel. The right front blinks, but it is irregular, I got nothing on the rear. I'm assuming that the irregular blinking is due to the short. I'm at a loss, everyone knows that pulling this dash is a complete PITA. Any suggestions, or known places where this wire shorts? Also a source for wiring diagrams would be nice, I've searched everywhere with no luck.

Truck is a 1993 F-250

 

[MtnHaul]

Couldn't the irregular blinking be due to a faulty flasher? Were any of the lights converted to LED?

 

[Thewespaul]

It could be your multi function switch is bad, the contacts corrode if trucks sit in humid air for a long time. If you have a short, you will either be popping a fuse or you will have unwanted power in an unrelated circuit. Sounds to me like more of a component failure. Check your grounds at the rear of the truck and make sure that’s not your issue.

 

[HicksNthaStix]

Couldn't the irregular blinking be due to a faulty flasher? Were any of the lights converted to LED?

None converted to LED, however when the flat bed was out on the wiring job was very sloppy. I will try a new flasher and see if that solves it.

 

[HicksNthaStix]

It could be your multi function switch is bad, the contacts corrode if trucks sit in humid air for a long time. If you have a short, you will either be popping a fuse or you will have unwanted power in an unrelated circuit. Sounds to me like more of a component failure. Check your grounds at the rear of the truck and make sure that’s not your issue.

Not sure if the truck has spent time sitting out not, but here in Tennessee our humidity is awful, so corrosion is certainly a possibility. I'll check that ground again as well. Thanks for the suggestions.

 

[SIKPUP]

My 93 F-350 with the towing package has a right and left fuses for the turn signals in the fuse box under the hood for the factory hitch plug , not the tail lights in the body/bed .

 

[Oledirtypearl86]

I'm with Wes I think it could be a ground issue especially where it's all scabbed together also check your light pig tails I have to resplice a new pig tail every couple of years on my flat bed they get full of road grime and always seen to hold moisture but I used dielectric on the last one and it's holding up better