Anyone else really enjoy making their own wiring harnesses?

I'm trying to tidy up my engine bay, and I really dislike the quality/appearance of the wiring for most aftermarket lighting. So for my raptor lights, I stripped all the plastic loom, the nasty sleeving, and the old connections (most didn't even have the rubber stoppers), and I did new sleeving, 16awg where I could, new connectors and new heat shrink. Very pleased with the outcome. All new wiring will go in this way, and I'll probably do what I can with the factory harnesses too.

 

Nice work. Maybe also post some before-and-after pics of the old/new harnesses as-installed in the engine bay.

 

I absolutely will. I'm waiting on some bus bars so I can have a single connection point for anything that needs the ACC fuse - hopefully only 1 add a fuse in the box. The old harness was basically just split-loom zip tied as out of the way as possible.

 

I watched a documentary once where these Japanese women would get sent these boxes from Toyota to their homes, in the countryside. They’d get together, make tea, chit chat and have a sort of ‘sewing circle’ putting together wiring harnesses. They’d mail back the completed harnesses and get sent more materials. It was a supplemental income, cottage industry type deal for rural folks.

 

Looks good. I just recently added an Auxbeam 6 gang setup to work out my lighting. I added ditch lights, and two lights in my back bumper - an amber chase light and a white flood. While I was at it, I redid the wiring for my light bar in my front bumper. Made a harness for the rear bumper and another for the ditch lights. I should've taken pictures of the harnesses as I was making them but didn't think of it until everything was in. These pics don't show the ditch lights, but you get the idea:



edit: This really wasn't that expensive or time consuming.

 

Just took a couple of pics of the ditch lights. You can see the waterproof plugs, which the rear lights have also. This way it's easier to replace lights if I decide to change or one dies.


All connections are soldered/marine shrinkwrapped. The ditch light harness took me 2-3 hours and the rear harness maybe 6, but that's because I had to invent the wheel.

 

Yeah it feels good when it's done and clean and you know exactly what's where.

 

Yes indeed.

https://www.tacomaworld.com/threads/1gr-fe-wiring-overhaul-a-slow-descent-into-madness.712981/

 

I've always don't my own harnesses but I also spent 15 years installing car audio so I'm anal about wiring, especially if I might ever need to go back in to check things or add more. I'm getting ready to add an auxiliary fuse box to clean up the wiring for my fog lights and aftermarket horns and to leave expansion room for what ever else I want to add.

 

Good code to follow for use in environmental extremes is the AYBC. I use most of their standards doing wiring on boats, motorcycles and for any 4 wheeled on or off road vehicles.

I believe one of those recommendations is crimped or crimped and soldered connections - ABYC 11.14.5.7: Solder shall not be the sole means of mechanical connection in any circuit.". Additionally, strain relief should be provided within 6 inches of the case termination. Also like to use waterproof crimp connectors and tinned wire. Use a proper crimp tool too:

 

Solder fractures in high vibration/high thermal cycle environments (aerospace, racecars, heavy industry). Properly crimped connections with a sufficiently high strand count for a given gauge are airtight and electrically solid. In fact, for this reason it is relatively rare to find a soldered connection at all in a high performance aircraft or a military combat vehicle, aside from electronics/avionics, which follow their own particularly demanding sets of standards (or sometimes don't - I spent a lot of time working with essentially COTS hardware that was simply R&Rd as a 'black box' for failure because it wasn't time effective to attempt to diagnose or repair them outside of depot level maintenance - hardware is cheap and there are never enough hands and brains in the field for wartime opstempo).

 

And salt corrodes the shit out of crimped connections. Had too many problems with that over the years. Solder doesn't corrode.

 

Plus good marine heat shrink.

 

I had a project, a previous someone made light harnesses using 6” pieces of stranded and solid wires, all twist and tape connections, pretty much nothing worked. I told the customer I’m not even going to try to fix that garbage, I’ll make all new everything.

The end result isn’t what I would call pretty, I was aiming at functional and durable, everything worked.

 

I would've used 18 awg. Less weight, thinner and easier to route, especially for LED's.

 

You're not wrong, but I'm happy with what I've been using. I have plenty, and it fits nicely into the terminals I have. I don't mind a little overkill for peace of mind.

 

Simpler and OEM like...

 

The problem is the lead free solder everything uses now, lead free solder has a tendency to crack with heat cycles and vibration. Leaded solder doesn't tend to have that issue.

That's why cracked solder joints are such a problem on modern electronics because they can't use leaded solder anymore.

I've yet to see a properly soldered connection using leaded solder fail

 

Yeah, brittle RoHS solder also has a ton of issues with tin whiskers causing shorts in miniature/micro scale electronics. I spent a long time dealing with that on a particular program, it was a nightmare until we figured it out.

I have actually seen leaded solder fail due to mechanical stress - it was in a larger (10awg) pinned connection in a shell that saw a relatively large amount of flex nearer to the connector shell. The pins were similar to DT "barrel" style pins, and the wire was soldered into the socket/tube end of the pin, which was clipped via internal features in the connector shell. I didn't put it together in the first place, so I don't know exactly how well it had been assembled in the first place, but it was a very sneaky failure in that it was intermittent and not apparent on visual inspection. It took re-pinning to see what had happened interior to the crimp, which was corrosion in the wire under the solder/inside the crimp. Extremely fine alkali dust + intermittent wetting will do terrible things to just about anything.

To be fair, I do believe the original mention of solder in joints here pertains specifically to mechanical connection, which I do think is the key detail:

I would never, for example, just butt or lap two wires together and solder except maybe on a bench-only circuit like a prototype or something. For anything installed for field use, I would always do e.g. a lineman splice for mechanical strength and then solder/shrink.

I think the bottom line/non-answer to the question at hand, as always, revolves around the application. In something like a 0 AWG crimped solid lug, solder is unnecessary generally and even undesirable depending on the application. For smaller open-style crimped terminals, solder is probably not going to be a bad thing.

 

OP, love the look of that harness.

I'm looking to build my first wire harness for 4 Baja Design Rock lights for my roof rack. I was originally going to just buy some 16awg outdoor speaker wire but after doing some research, it seems like I might want some higher quality wire for when it enters the engine bay and for UV/weather resistance as it will be on the roof rack. Looks like most nice wire is all single run, no 16/2awg. I'm looking for some recommendations for wire brand/type and loom brand/type (split loom?).