Damaged trailer wiring harness

Crimp connections even correctly done are a poor method of repair for anything that is going to get constant flexing and vibration. Considering what you pay for a rig, I seriously doubt that $25 for a new cable/plug is going to break the bank. If it is, then maybe another past-time is in order. There are volumes written on forums about problems caused by trying to do a repair on the cheap. Do it right and do it once.

Those are scotch loks, aka junk. A butt connector crimped with the proper crimping tool--NOT a pair of vise grip pliers--and covered in shrink tubing will last a long time, and is less prone to failure than a solder connection in this kind of application. As someone else noted, solder is an excellent electrical connection, but a poor mechanical one. That said, I'd go with the advice to simply replace the entire cord with one that has a molded on connector. Do it once, be done with it.

mchero wrote:
I should have been more specific in my post.

I was referring to

Also when I refer to soldering I'm referring to PROPERLY soldering joints. NOT cold soldering!

Shesh!

These are aka "Scotch-loc's". And you are right about how bad they are. They are used because they are quick to use.

I should have been more specific in my post.

I was referring to

Also when I refer to soldering I'm referring to PROPERLY soldering joints. NOT cold soldering!

Shesh!

Northern tools has an 8 foot cable with 7 connector plug for about $25.

Worked perfectly.

Doug

Be sure to tie the new cable or section up to or inside the frame so it doesn't get caught on anything.

As cheap as a cable with molded plug is, trying to splice it is the last thing I would do. That 7 wire cord is subject to constant flexing and even the best done crimp connectors are subject to fail. If it's in a boat or RV where it's secured after repair, that's a different matter and splicing is OK. Replacement of the wire/plug assembly with properly done connections at the junction box and secured with strain relief is the appropriate way to fix it. Anything less is going to be a waste of time.

If I were to splice it I would use uninsulated crimp splicers and srink tube on each joint, and stager the joints. Then srink tube over the whole cord.

I prefer the pre built replacement with the end already on it. It's just easier and quicker install. I just had to replace the one on my car trailer, it was having an issue staying in the plug, after inspection the little tab on the moulded end wore out and the cable had seen a good hard 10 years of lift with cracks and other issues.

As for solder vs. butt connector. I go with the connector every time, but I dont use the standard ones you find sitting in a 4 dollar box in walmart. The ones I use are meant for weather resistance and heat strink plus has adheasive to keep the whole thing together. Been using it for years with no issues of corrosion or splices failing.

Solder is a good electrical connection, but does not make a good mechanical connection. Also, if you aren't proficient at soldering, a cold joint can cause future issues. I've been using crimp on connectors for close to 20 years and have yet to have one fail.
A crimp connection, properly done with good crimpers on clean wire, and covered with heat shrink will last indefinitely.