Ok ran some tests before my test light blew up.....

All test good from vehicle

Each of the lights has 3 male ends which plug into the light

Right side....2 studs are hot
Left side....1 stud is hot.

All in all I believe only 1 stud should be hot on each end.....then when the brakes are applied I should have 2 studs hot on each end....am I correct?

And if I only have 1 hot when brakes are applied then I've got a wiring problem between the 2 I'm assuming.

1 wire is parking light, 1 wire is brake/blinker, 1 wire is ground. Disconnect all your lights. To test wires, turn your key on. Turn the parking lights on. Brown wire is parking lights,although yours may be diff. It depends who wired the trailer. Yellow is one side blinker, green is the other side. Turn blinker on and test wires before they connect to light. Do the same to the other side. When using the test light make sure the alligater clip has good contact to the trailer. Touch the wires with the other end and see what lights up. Ittook me a long time to figure mine out. I don't understand electricity to well, along with many other things! Hope this helps.

If you have a low curent battery charger and get tired of running to the truck all the time ground it to the trailer and connect the hot to the wire you want to test. in the plug end witht the three studs one is ground, one is marker, one is tail. If both are lit up besides the ground check where they are connected at to the pigttail by the light. Also are your wires ran in the frame of the trailer or exposed on the under side? if exposed check where they weave in and out of the wire holders for a rubbed spot in the marker and turn wire colors. are the housings sealed lights where you throw the whole unit out or is it a bulb style. If a sealed then its in the wiring, bulb type check for corosion in the taillight housing where the bulb sits at. Also check to make sure that at the light the ground is good, it might look like it, but take it out and wire brush that spot and reinstall again.

Your right....I have brown yellow and green.....going to try a few more tests now and try to find out whats up.

Ok here's the prob now.

parking lights all work

apply brakes and the right side will not brighten, nor will the blinker work, right side.

Left side is all fine.

problem solved.

Disconnected the light and took it up to the housing and checked it. Apparently the Green wire is bad or something. I'm going to run a whole new wire down the trailer and that'll solve the problem (I hope)

Thanks for the help everyone and especially Forumla, I know I had you scratching your head a time or two

Thats the problem with dunking trailers, everything gets wet. Some people test lights by poking the test light into the wire to make contact. This leaves pinholes in the wire to allow water to get in and corrode the wire. It can happen anywhere in the wire and is drives you crazy trying to find the problem!

Yeah that might be my next prob....I've cut the wires and put electrical tape back on them. I'm pretty sure water will get in there so I might have to come up with a better solution.