How do you wire? solder, crimp, heat shrink, scotchlok


Active Member
Aug 23, 2007
Los Angeles
I am redoing the brakes and wiring in my pup as well as installing new brake controller and wires and plug in new TV.
Got the brake controller and wires from etrailer. Brakes and wires from R&P carriages. They all supplied me with both scotchlocks and crimps.
I have read the best connection is to solder. I have never done that before. Is it necessary? What do you do?
I was thinking of just crimping and then maybe cover with electrical tape? or maybe try heat shrink?

Any suggestions?


Super Active Member
Jul 8, 2008
East Central Illinois
Yes, the best method is to twist the wires together and then apply a little bit of solder to it and then wrap in electric tape.

The second best, IMHO is to simply twist the wires together, fold the twisted leads in half and then tape. This is what I do 99% of the time. If I am splicing into a wire I will take a utility knife or exacto knife and carefully peel away some insulation and then wrap the splice around that section a couple of times and then wrap it up in tape. The only time I use a scotch lock is when splicing into wiring that is very hard to get to.


Jun 9, 2008
Valdosta(Hahira)- GA
I use terminals and crimp/heatsink almost exclusively.... I just finished wiring my TV harness and electric brakes and used that method.. at the end, I ran out of heatsink and had to use tape on the crimped terminals.... but only a few.. I had to use one scotchlock when connecting the brake controller to the cold side of the brake pedal because that's the only way I could get to it..

When I rebuild the pup I'm going to re-wire the whole thing, the factory job is atrocious and is all scotch-locked with the exception of the grounds which the factory just wrapped them all, bare-end wires around a screw that is attached to the frame!.. When I re-wire I MAY solder, but I will probably just use terminals... crimp and heatsink.. I plan on putting in a distribution block for the grounds and 12v...


Ottawa, Ontario, Canada
Aug 3, 2008
Soldering works well when you have room to work, and assuming that you are comfortable and practiced at it. Otherwise, you run a real risk of overheating the wires, compromising the insulation or other connected components.

Crimp terminals, properly selected and sized, are my preference in most situations. They will give a good solid connection, and if enclosed do not really require taping or shrink wrap although I know many people do it as much for neatness as anything. If there is a realistic risk of exposure of the join, it is definitely advisable to heat shrink or tape.

Wire looms are also your friend. Neatens, helps prevent chafing of insulation, and helps prevent loosely placed wires from shifting and getting crimped in / by something.

Scotch locks are definitly a last resort.


Waterford Ct.
Oct 3, 2007
Waterford, Ct
Solder important connections, or use the vinyl (semi clear) heat shrink connectors or terminals. The hard plastic connectors split.


Active Member
Jun 25, 2004
For anything under the trailer I like to solder and shrink wrap the connections. But if the wires are black with corrosion I use crimp connectors and liquid tape.


Active Member
Jul 3, 2008
I work for a major engine manufacturer and do a considerable amount of electronic and wiring work for engines. I quit using solder for splices due to the vibration which would eventually crack the solder in harnesses. I personally like multi-link connectors, PM me for a website where they can be ordered if interested. These are a crimp butt connector with an adhesive heat shrink and solder ring. You get the mechanical connection with the crimp, the electronic connection of the solder, and the protection from the heat shrink/adhesive combination. I've been using them exclusively for a couple of years now and have yet to have a failure. They are also what I used when wiring my trailer brakes.


May 11, 2009
I just finished doing the hitch, wiring harness and brake controller. Used crimps for all but the splice into the brake switch wire - that one I soldered, just to make sure.


Active Member
Jun 4, 2009
San Diego, CA
I Solder all my connections and I mean ALL! Then I use a clear heat shrink heat shrink, so that way if you have a problem later you can always see through the clear shrink wrap to see if the connection is good.
And I have never seen a good solder joint go bad!
I have seen crimp connections go bad quite a bit....


Active Member
Mar 16, 2008
Ontario, Canada
Waterproof Heatshrink tubing (yes there is a difference...waterproof heatshrink actually has an inner coating that melts to seal the connection) works well if your connecting two wires, but not so well beyond that. Mechanically the joint till stay together, but water will get in. If you solder and heatshrink a connection of more than two wires make sure to apply a little automotive goop to the end of the connection with more than one wire. Never use electrical tape where water can be present, or where big temperature fluctuations occur (like outside - lol) 'will' eventually fail. Alternatively, those scotchlock connectors can be made to work in a pinch by coating and sealing them in hotmelt glue or Automotive goop once the connection is made.


May 21, 2009
crimp and silicon. I work in high humidity areas and not using a silicon to make the connection water proof (especially in the outside of the pup) is a broken lead waiting to happen. just my thoughts


God bless the U S A
Mar 22, 2009
jwolfe01 said:
You must not have ever worked on boats that get used in saltwater then. [LOL]

A good solider joint that is sealed well will only brake if bent at the joint or constant pulling of the joint is presant. Salt water and boats have nothing to do with trailers so bad remark and i have never seen a solider joint fail and i work on the F-18 Super hornet USN


2004 Jayco Qwest 10K
I solder everything unless I need to crimp on ends that need to be unplugged. Inside I tape if it is outside I heatshrink. No matter what connection, the key is supporting so the connection isn't flexed to the point of breaking.



Active Member
Aug 13, 2008
Check out these connectors
I think this is what jenoble99 was referring to. We have used these on semi trailers for years. They take all the abuse that an over the road trailer can dish out with no problems. They are a bit expensive. They can be found at NAPA or from McMaster-Carr. The heat shrink on them is the correct type for exterior pup use as it has the hot melt adhesive inside that seals the connection. if you use mutiple wires in one connector, use some liquid electrical tape to seal between the wires. Don't try to heat them too quickly or they will leak solder out insteasd of it going intop the joint.