Hello The right turn signal failed on my trailer, it would not blink. All the wire insulated butt connections with heat shrink ends were very good! So I finally traced it down to the 16 guage green trailer wire that goes to the right turn signal, which the stranded copper wire was very brittle and contained a white substance inside the wire jacket! It suffered from sacrificial oxidation, commonly known as “copper rot”!! Budget wire harnesses use untinned copper and porous insulation, allowing capillary action to wick road salt and water! I went crazy and spent $16.99 for a new light assembly and $3.99 for new 10 pack of insulated Butt connectors with heat shrink ends before I found the real issue! I tested the old light assembly still work fine! The harness and lights and connectors were all purchased at Harbor Freight. I tested the old light assembly still work fine! The harness and lights and connectors were all purchased at Harbor Freight. When I installed the HF wire harness on my trailer I made a big loop of extra wire with a wire tie on it just before the tail light so I had to cut it back a lot when reconnecting it and it worked!! Also you can see in my pic above that I ran the white ground wire to a black wire with a round connector on it to the trailer frame with a stainless steel screw that fights the rusting. Before I screwed it in, I wire wheeled the chassis to remove all the paint for the very best ground connection. See bench test pics of old HF Tail Light below How can we prevent this in our trailer harness wiring?? Would this HF protective wrap help?
Or Would this tape wrap help? https://www.amazon.com/gp/aw/d/B0BW...&pd_rd_r=fb537775-4369-4100-b7d7-62329246dcd7
Sounds like a new/better harness is in order? You said yourself budget harnesses have porous insulation? Not sure I've experienced that. I would guess maybe a rock or something else compromised the insulation in one spot, allowing corrosion to get in? If the harness is junk, replace it. If you think something compromised the insulation then MAYBE that plastic wire loom stuff would help. Then wrap the insulation with tape like factory harnesses are.
Hi Jeff Thanks for your comments. Believe it or not, I did get this newer 16 Guage wire harness, which is so much better than the old one where it was broken every time I used the trailer! The original from harbor freight was really bad so about 3 or 4 years later I looked all around for a heavy wire harness and then finally went to HF who upgraded to this one which is heavier and a lot better. After I removed the old light I found the brown wire next to the green wire in the harness still had a nice shinny stranded copper wire at the end. So I suspect the green wire somehow got moisture and road salt damage. Also I noticed most cars which have good heavy copper wires still have a wrap not only to bundle the wires to different locations but mostly to protect against road salt and moisture. I did have a small cit that barely exposed some copper up near the trailer hitch so I replaced the insulated bit connector and heat shrunk the ends but that did not fix it. So I cut the green and brown wires and removed the old light and that is when I found the corroded and brittle copper wire in the green jacket. In this case all the butt connectors looked good but there is a possibility that where the crimp is that moisture got in. That is a very small area. So still not quite sure how the damage got in, but by cutting the wire back, it was good enough to throw a new butt connector on and get it working. Maybe a good test for the future is to wrap the connectors and and wires coming out back a little way and see if the wires hold up better. Thanks again for getting me thinking.
I've never seen porous insulation, but it wouldn't surprise me that wiring from HF could/would do that! Some of it I've seen there was really crappy! I'd say it's more likely moisture got through a crack, or a connection... hopefully nobody was probe testing the wire at some point...that's always a mistake in the long run. While on the topic... 904K views · 7.9K reactions | Simple and easy solution #tools #gear #construction #wires | Stanley "Dirt Monkey" Genadek
