jboIND

I recently had an old tandem axle trailer of mine painted and I'm in the process of rewiring it. I got the new breakaway hooked up and it is working. The brakes are working on both axles. The brake lights work. The clearance/taillights work. Both turn signals are working. Here's the problem though. The turn signals won't work when the taillights are on. But when the taillights are off they do work. What am I doing wrong here? I've been over everything several times but I know there has to be something missing or wired incorrectly. I eventually just quit after getting frustrated. I'll be sore in the morning though after crawling all over that thing.

DYNOBOB

What type of tail light are you using? Led/regular? If it's a three wire set up to one light how do you have it wired?
Bob

jboIND

They are LEDs. I have each light individually grounded. One wire to the harness for left/right turn signal. And then the last or third wire is connected to the clearnance wire coming off the plug. Which I have all my other clearance lights coming off of that same wire. I used 14 gauge on all wires except ground and battery I used 12.

dozer12216

Do you have a ground from trailer to truck? Truck frame and especially bed are not good grounding places. Take brakeaway battery out of picture for diagnois purpose.

DYNOBOB

I think your problem has to do with how the brake/stop/turn lights are wired. You should have three wires going into that light and I don't think they should have a wire going to ground directly. One wire is brake, one is parking, and one is turn. When the turn signals and brake wires are at rest they are the ground for the other wire. I'm not positive this is your problem but it may be.
Bob

Foxborough

My vote is bad ground. The turn signal needs only "x" amount of amps to run. When you turn on the lights and the turn signal, you need "x+x+x+x" amps and the crummy ground will not allow that much current. So all the lights see LESS voltage. Just the trailer connected to the truck will not be good enough ground. A 12v source is not a lot of energy. Good luck.

carl48

dynobob you were close one wire from each led goes to ground one hot led go's to turn sig and another one go's to the marker circuit jboind you need a volt ohm meter any way just check from frame ground to each hot lead on the led and to each ground lead

jboIND

Well I worked on this thing since 7 a.m. Just now finished it and everything is working. First off, like most of you guys stated --> bad ground. I ended up yanking all the wiring and starting over without the breakaway hooked up. Grounded everything properly. Ran each wire to the trailer plug individually before concealing it underneath the trailer. Come to find out there was a short in the harness off the truck. Everytime I would hook up to the trailer it would blow a fuse on the truck. Took me a while to figure that out but I got it fixed. So at about 3 or 4 pm I got everything working and started to run the wires through the 1/2 metal piping I bolted to the frame underneath the floor. Just my luck. While dragging one of the wires through it got caught and the sharp edge of the pipe sliced my left turn signal wire in half. I didn't realize that until I hooked up to the truck again. At this point I was half ******. But I eventually found where is was cut and reconnected it. All in all for never doing this before I think I did a pretty good job. I did take two full days and a lot of trouble shooting, but it turned out nice. Putting new floorboards on tomorrow and then Thursday its going back on the road for work use. Just wanted to thank everybody for help. Once I get the wheels painted I'll post a couple pics to see what ya'll think.
Thx, Jay

jboIND

Oh by the way. It is an old Hudson trailer dad bought new in '84. This is the first time anything has been redone on it. I pray to god I don't have to mess with it again until 2030. LOL.