Here's a good question for you guys. i'm not sure what happened here, but, it happened, so....

Okay, so just got done doing a simple trailer re-wiring. New lights, and side markers. Just the basic stuff. I don't think I screwed up the wiring. It's pretty simple, color coded, it's not rocket science. Yellow to yellow, green to green, brown to brown, white to ground, self grounding lights. Trailer lights on my jimmy work like they are supposed to. Checked them with a test light. So, the problem is my wiring, but I don't see what I screwed up...

The problem is, when hooked up to my jimmy, the tail lights (running lights) turn on, but the side markers do not. They are hooked up to the same wire (brown). Brake lights do not work, and turn signals do not work, however, when you turn on the right turn signal, BOTH lights flash. With the running lights off on the jimmy, the hazards flash on the trailer like they are supposed to.

The trailer is fairly rusty, its not a show queen for sure. Think that the grounds on the lights could be at fault for this? It was my first idea, but I thought I'd ask see if anyone else had any ideas. I figured I'd sand down the rust on the ground locations and see what that does, but I won't be doing that until tomorrow. Just thought I'd ask if anyone else had any ideas.

It really sounds like a ground problem to be honest. Make sure that all lights that need to be grounded are and that the ground wire is grounded to the frame and then connects to the pigtail. This way when you connect you trailer via hitch and wiring you are grounding everything through the wiring and the hitch. Make sure you ground to bare metal as well.

I figured as much. Just making sure I had another head in on this. I'll be sanding all the grounds down to bare metal tomorrow and we'll see what happens with that.

Alright now I'm lost......
Sanded down all the grounds to bare metal.

Now I have:
Tail Lights
Left Turn Signal
Hazards

I do NOT have:
Right turn signal (well, I do, but, when I turn on the right signal, it blinks, but so does the left turn signal, just not as bright. Kinda like it's grounding through the left turn signal)
Brake Lights
Side Markers (interesting here because these are connected to the tail light wire, and the tail lights work)

I have power at plug (trailer end) where everything is supposed to be. I have power on brown wires (tail lights) at the back of the trailer when the tail lights are on. With the brake lights on, I do not have power at that wire, either side, but there is power at the plug still.

What are the chances two different wires (the yellow and the green) have brakes or cuts in them to cause them to short out?

Its very possible. Especially if you have use old wires. There could be small nicks and cuts that would allow it to short out or loose contact. Also Try checking everything by testing from a battery instead of your truck. That could also be a small problem there. Electrical wiring when it comes to trailer lighting is my enemy. I swear there are times that it kicks my tail all over the shop until I finally figure out its something simple.

I am sure its something simple. If you are using the harness that came with the trailer originally I would try junking it and running all new wiring. Something as simple as someone else making a mistake wiring or using a test light to check for power can cause a whole lot of issues. When I run into these issues with the trailers at work (I usually do as most of the wiring repairs are hack jobs to get equipment back on the road) I usually end up running all new wiring in the section of the trailer I am having issues with.

If you need help while you are working on it u can IM me on aim or yahoo as I am on most of the time.

Somebody just told me that if you have a tilting trailer (like I do), that you may have to run a ground wire from the back of the trailer past the tilt mechanism. I'm gonna give that a shot before I go crazy any longer.

I had a problem with our trailer wiring a few months ago..

Everything was good, all wiring was redone right, but it kept popping fuses @ random & lights were inconsistent..

It ended up being a short INSIDE the 4 prong trailer plug... Where the wires attached to the prongs inside the plug, there was a few strands of wiring that would touch the other terminals...
I had to actually take the plug apart to find it..

GOod luck.

Thanks for the idea, but I already tried that. I cut off the plug and put on a new plug, but i'm still having the same problem.

I'm going to try to ground wire "jumper" and see what that does. Couldn't do it till this weekend, plus I had to go buy a new charger for my cordless drill since I lost mine, but these damn batteries lasted so long for me. Hehe, I haven't charged these batteries in 6 months, and thats WITH drilling into metal, automotive use, wood, screws. 6 months on two batteries! I couldn't believe it.
Anyway, gonna happen this weekend no worries. I'll let you guys know if the jumper fixes it.

here is a link to try. sounds like you have a wire hooked up back wards on the right side or the ground at the front of the trailer is not making good contact. one other thing is are you sure that the wiring harness is wired correctly on the truck side? like have you tested it on another trailer?

but thinking about it sounds like the the green and brown wire are switched on the right side or have a bad ground. check inside the light assembly its self and make sure there is not a crushed/crossed wire.

link

Nope, the wires were all connected correctly. And the vehicle wiring was right on too.
Good news though I fixed it today.
Turned out it WAS a ground problem. I sat down today, watching the turn signals flash, and realized, they were grounding through the bulb on the other side. All of m grounds are down to bare metal, but I guess since this trailer is a tilt/folding trailer, somewhere between where it folds there is a bad connection.

05lssport told me to try hooking up a jumper wire from the a frame before the tilt mechanism, to the trailer frame after the tilt mechanism. After I did that, my side markers started working, which clued me into the ground issue. After that I ended up running each rear light, it's own ground wire, up to the side marker grounds, and bam, everything worked perfectly.

Really BIG thank you to all you guys for the help. Thanks everybody for your suggestions.