Check your trailer wiring

[Elkins45]

I went fishing on Thursday and left before sunrise. All the trailer lights were working perfectly. When I turned them on for the trip home the marker lights didn't come on. The stop/turn still worked and thankfully it was a short drive so I made it home without a ticket or an accident. I tested the truck the next day and the trailer circuit was dead, but fortunately it had popped a fuse rather than fry something expensive. It took a bit of searching to find the fuse but that fixed it. I was smart enough to text the trailer and find the short before just plugging it in again.

The trailer is a Bear brand made in 2006. It turns out that they did the wiring by just torching a hole in the steel tubing wherever a wire enters or exits the frame. The edges of all those holes are exactly as ragged as you would expect torch cuts to be. Between 19 years of weather deteriorating the insulation and the mechanical rubbing where the wires entered the frame there were two places with exposed wires causing dead shorts. Honestly as bad as the wear was I'm amazed they hadn't failed long before. So I spent my afternoon yesterday completely rewiring my boat trailer. I elected to run the wires along the outside rather than through the frame so I hopefully wouldn't have the same issue again. I know it doesn't look as clean but I don't really care about looks on a boat trailer LOL.

Everybody checks if their trailer lights function before going on a long trip, but how often do you really look at the wiring? It might save you a big headache to check any entry or exit points for insulation failure, and maybe even give the wires a wrap of electrical tape at those points.

 

[supton]

The cheap HF wiring I've had in the past wouldn't make it more than a few years, so it was often "new-ish". I used to carry a set of magnetic lights so I could always toss on, just in case.

If I ever get a towing set up again, I might make my own wiring convertor, and figure out how to detect if a light is out--along with current limiting so as to deal with shorts. Maybe... lots of good intentions, but a lack of time & desire.

 

[Arc]

I went fishing on Thursday and left before sunrise. All the trailer lights were working perfectly. When I turned them on for the trip home the marker lights didn't come on. The stop/turn still worked and thankfully it was a short drive so I made it home without a ticket or an accident. I tested the truck the next day and the trailer circuit was dead, but fortunately it had popped a fuse rather than fry something expensive. It took a bit of searching to find the fuse but that fixed it. I was smart enough to text the trailer and find the short before just plugging it in again.

The trailer is a Bear brand made in 2006. It turns out that they did the wiring by just torching a hole in the steel tubing wherever a wire enters or exits the frame. The edges of all those holes are exactly as ragged as you would expect torch cuts to be. Between 19 years of weather deteriorating the insulation and the mechanical rubbing where the wires entered the frame there were two places with exposed wires causing dead shorts. Honestly as bad as the wear was I'm amazed they hadn't failed long before. So I spent my afternoon yesterday completely rewiring my boat trailer. I elected to run the wires along the outside rather than through the frame so I hopefully wouldn't have the same issue again. I know it doesn't look as clean but I don't really care about looks on a boat trailer LOL.

Everybody checks if their trailer lights function before going on a long trip, but how often do you really look at the wiring? It might save you a big headache to check any entry or exit points for insulation failure, and maybe even give the wires a wrap of electrical tape at those points.

Smurf tubing is the way to go on a trailer. Although its plastic it does offer good protection.

 

[AZjeff]

Huh?

Smurf tubing is the way to go on a trailer. Although its plastic it does offer good protection.

 

[Arc]

Huh?

sorry, its just a term for the blue plastic flex tubing.

 

[D60]

Yep, the slag from the blue wrench is so sloppy. I re-drill holes correctly and stock grommets with enough gap to handle at least 3/16" w.t.

I run fresh wires hung from rubber insulated clamps.

It's work but done properly saves you headache for decades to come.

I would like to find most trailer builders and fry them (slowly) under a giant magnifying glass.

 

[kschachn]

With the ridiculous number of mice in my area I do check it all every time.

 

[Elkins45]

With the ridiculous number of mice in my area I do check it all every time.

The mice were apparently too busy making a nest with my flotation vest to bother with the wiring.

 

[Elkins45]

Smurf tubing is the way to go on a trailer. Although its plastic it does offer good protection.

My experience is that it doesn't hold up to UV very well and crumbles in a few years.

 

[AZjeff]

Before a 3000 mile trip in May with the travel trailer I checked all the lights and did the usual check the electric brakes by pulling the lever on the controller and feeling the trailer slow the truck. Good to go. After coming down a mountain pass in Colorado I checked the brake drums and found 2 cold. Discovered that the splice crimp connectors used to connect the wires at the back of the drums had apparently cut the wires partially and after 8 years one of the wires on 2 brakes had broken apart. Also found while doing a field repair that the grommets in the holes in the axles that the wires go from left to right side had deteriorated and 2 were missing and were rubbing bare places in the insulation. Got some electrical tape around the wires as a temp fix and made the rest of the trip with 4 trailer brakes. Never considered visually checking the brake wiring.

 

[Arc]

My experience is that it doesn't hold up to UV very well and crumbles in a few years.

I always used SO cord. It can be picked up at any supply store with the correct gauge wire and number of conductors. There are many options to protect the wiring.

 

[D60]

I stay with SAE standard colors for the wiring. Not only will the next guy thank me but I'll thank myself if I ever have to troubleshoot.

My only pet peeve is the two different layouts for 7-pin between SAE and RV. So dumb and one should be universally eliminated -- I don't care which.

 

[nwjones18]

Good catch. I’ve blown fuses before backing my boat trailer in the water with it still plugged in

 

[Elkins45]

I stay with SAE standard colors for the wiring. Not only will the next guy thank me but I'll thank myself if I ever have to troubleshoot.

My only pet peeve is the two different layouts for 7-pin between SAE and RV. So dumb and one should be universally eliminated -- I don't care which.

You make a good point about the wire colors. I added some extra lights when I installed guide poles. One side had red and green wires, the other had purple and silver. I didn't bother to record which was brake and tail but fortunately I could trace them back to the correct brown, green or yellow wires.

 

[Donald]

You make a good point about the wire colors. I added some extra lights when I installed guide poles. One side had red and green wires, the other had purple and silver. I didn't bother to record which was brake and tail but fortunately I could trace them back to the correct brown, green or yellow wires.

View attachment 298242

I have guide poles for my trailer but they are in the garage somewhere. My boat gets loaded onto the trailer via a huge forklift. I think the guide poles would be in the way of loading.

Trailer has never been in the water to launch or load boat.

 

[Elkins45]

I have guide poles for my trailer but they are in the garage somewhere. My boat gets loaded onto the trailer via a huge forklift. I think the guide poles would be in the way of loading.

Trailer has never been in the water to launch or load boat.

If my boat has ever been on a forklift it was at the factory. Those guide poles are a real boon when trailering by yourself in strong winds or current.

 

[Donald]

If my boat has ever been on a forklift it was at the factory. Those guide poles are a real boon when trailering by yourself in strong winds or current.

It's the way they do things at a rack storage marina.

 

[D60]

While I realize this is far from rocket science, I am far from a rocket scientist and suffer from C.R.S. Thus a couple decades ago I cut this out of 4WOR or Petersen's and taped it to the shop wall. Above that is sheetmetal gauge thicknesses

 

[burbguy82]

I went fishing on Thursday and left before sunrise. All the trailer lights were working perfectly. When I turned them on for the trip home the marker lights didn't come on. The stop/turn still worked and thankfully it was a short drive so I made it home without a ticket or an accident. I tested the truck the next day and the trailer circuit was dead, but fortunately it had popped a fuse rather than fry something expensive. It took a bit of searching to find the fuse but that fixed it. I was smart enough to text the trailer and find the short before just plugging it in again.

The trailer is a Bear brand made in 2006. It turns out that they did the wiring by just torching a hole in the steel tubing wherever a wire enters or exits the frame. The edges of all those holes are exactly as ragged as you would expect torch cuts to be. Between 19 years of weather deteriorating the insulation and the mechanical rubbing where the wires entered the frame there were two places with exposed wires causing dead shorts. Honestly as bad as the wear was I'm amazed they hadn't failed long before. So I spent my afternoon yesterday completely rewiring my boat trailer. I elected to run the wires along the outside rather than through the frame so I hopefully wouldn't have the same issue again. I know it doesn't look as clean but I don't really care about looks on a boat trailer LOL.

Everybody checks if their trailer lights function before going on a long trip, but how often do you really look at the wiring? It might save you a big headache to check any entry or exit points for insulation failure, and maybe even give the wires a wrap of electrical tape at those points.

Trailer wiring is notorious for being janky. Almost anytime you have a blown fuse, it is either a hot to ground of worn electric brakes. I built my own trailer years ago, and have had no issue. I use of the shelf wire, loom, grommets, and hangers. No issue, other than when I hit something and broke the light off.

You would do your self good to go from stem to stern and check for where wires are secured and going through the frame. Remove and clean your ground while your at it.

The trailers I have bought in the past were Kaufman brand. One of their factories is right around the corner. I opt for the deluxe version, that comes with a fully loomed, taped, and USA made harness.

 

[4WD]

You make a good point about the wire colors. I added some extra lights when I installed guide poles. One side had red and green wires, the other had purple and silver. I didn't bother to record which was brake and tail but fortunately I could trace them back to the correct brown, green or yellow wires.

View attachment 298242

I have done this to have at least something that never hits saltwater …
Recently with LED bulbs - have even clipped some direct to the boat’s battery - in the end - 2 or 3 systems trying to be safe and avoid tickets