This Old Trailer: Finding and Fixing Wiring Shorts

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Finding and Fixing a Wiring Short Episode of This Old Trailer

Today on This Old Trailer, we are going to discuss electrical shorts on the trailer itself. Basically we are going to talk about if you plug up your trailer and you find out that you have a blown fuse and the tail light does not work, the running light does not work. We will go through this trailer we have here and try to find some problems with it and show you what to look for. Basically when you are dealing with a short you are going to look for physical evidence. And that means tracing the wire from the front all the way out back. So what is going to happen is basically we are going to start at the plug. Generally it is going to be somewhere down here that has a problem like it has extra extra long length here and it is going to be dragging on the ground so it gets some road rash in there.

Your running light and your ground wires could fray and touch each other causing a short that way. Just work your way on down and then a lot of times the wire lays against the steel of the trailer. Sometimes it is a vibration like this will cause that problem also. Or one of the wires, part of the wire will grind against the frame causing a short. There is nothing here so you just keep working your way down where the wire goes through the loop here or through the hole in the steel. If it is really tight it could vibrate and cause a short that way. Which is usually not much of a problem. Whenever there is wire lying on metal somewhere, always check there first for a short. And you can not really see it. Maybe just take your fingers and feel the wire. If you feel anything that is out of place, and we can feel there is something right here.

Let us pull it out and take a look. It looks like the gray wire has got a nick in it. It has been like that for a while too because it is a dark color it is not a shiny copper. All right we will go ahead and give this a quick fix. Basically we are just going split the brown wire away from the other two. And just pull it away just to get it started just like I did. Okay. And sometimes there is a small nick you can probably just get away with just cutting it in half and stripping the wires a little bit on each side. If you have got enough wire you can actually go ahead and just slice the butt connector right into place. If it was a little farther apart or a really big section like we are dealing with here you might want to go ahead and just put a small section of wiring and two new connections in there too. And this is right at the end so since these are kind of corroded up and your fresh wire is here, it is better to connect to that so let us go ahead and pull it out a little bit more and we will just put a new section in. Again, if there is just a one time deal then this is fine but if you are going to have like three or four of these places in your trailers, especially an older one, that has been sitting for a while, you might want to go ahead and just replace the entire harness because the more connection you have the more liability one of these coming loose. Start with fresh wire.03:27.

And actually this type of short is a perfect example of an intermittent short. Or sometimes you go down the road and you blow a fuse and then you put a new one in and it does not do it for a while, that is because these wires have been bouncing back and forth on the frame so when it hits the right bump, they will short out and you will not know what is going on. Okay, and we will just go ahead and just cover up our connection from the electric tape and we will give it a test. And this is only for our running light circuit. The short one that will not bother any other instances of left turn or right turn both have their own fuses on the vehicle. All right, once you have got your connection made, then it is a good time to go ahead and try it again. Now if this does not work again the chances are you might be dealing with another short somewhere else down the line. Chances are it is usually just one short causing the problem. We do not have our truck handy, we are just going to plug this into our own power supply. You could easily do this at home with a couple of wires coming off the back of your towing vehicle and just put the wires to the correct terminals temporarily testing it that way. All right, we have got our power supply on. We have got the running light circuit turned on. And so far it has not been shortened out but I think we are good with that circuit. It is always a good idea to inspect the rest of the wiring just in case. The same way we did before. 05:24

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