Harness wiring.
 

I want to redo some of my engine bay wiring.

Where can I get the Mazda OEM harness connectors? What is assembly like? Difficult? Horrible? Easy? I ask about these because I have a few connectors where the wire is exposed at the connector. I would prefer to redo the connector instead of hot glue gunning the exposed wire.

Will it cause any wierdness if I extend some wires for stuff like the CAS, knock sensor, fuel injector wires, etc?

Is it fine to solder/shrinkwrap? I fucking hate crimping.

My engine bay is clutterbombed with wires and I want to clean it up.

In for relevant info. Opening my hood makes me want to cry.

My CAS wiring is extended, no problems so far.

i ordered some COP plugs from ballenger motorsports and they are new weatherpack connectors.

I messaged them and they said if you contact them with the year, make, model, any markings or manufacturer stamps, size and pictures of the plugs you need they would be able to help you source them.

This is what i am doing for my 2002 VVT swap engine harness.

I also hate crimping and use solder/heatshrink exclusively.

For connectors with exposed wires:
Unwrap the harness tape and cut the offending wire further back, slip on heatshrink to cover the exposure. Add a second piece of heatshrink and rejoin the cut wire. Re-wrap the harness.

Or:
It is possible to disassemble most connectors, you just have to get creative in finding the lock tab. Once you get it out, cut and resolder the offending wire.

Wow, that's a great idea. Will do that today.

the only problem with solder is that a car is full of vibrations and wires like the engine harness will move and the solder will break over time.

i dare you to open any cars factory harness to find no solder anywhere.

you will likely see very specialized crimps which are made of a decent guage metal strap. (not like a butt connector, but its a similar theory with no chance of pull out.

Do you have any pics of these? I hate butt connectors.

There are a couple of lines in the factory harness which employ shielding of some kind, typically not in the form of a tight coaxial cable (like the one DIY rather annoyingly supplies for use on TachIn) but rather a conventional insulated wire with a loose jacket around it. These are mostly the low-voltage analog signal lines, such as the O2 sensor and the knock sensor. For short distances, and away from things that generate noise such as electrical motors, ignition wires, etc., you're fine.

While some folks think soldering is evil in a car, I vastly prefer it to using the relatively low-quality plastic barrel connectors that most folks associate with "crimping", particularly if you aren't using a decent quality ratcheting crimp tool, and especially in environments where the connection is going to be exposed to moisture or other corrosive factors. A soldered and shrunk connection is much less likely to fall apart or develop a high resistance due to oxidation than a butt splice.


Open up the stock fuel injector harness on any '90-'93 Miata. The banking of the injectors, as well as the commoning of their supply wire, is done with soldered connections wrapped with black vinyl tape.


We've had this debate before. When using the sort of crimp terminals and tooling that OEMs and major manufacturing facilities have access to, with double-foldover two-level crimps which also strain-relieve to the insulation, they're just peachy. But most folks don't own the proper tools to make this sort of termination, and for critical signals I'll take a soldered connection over one using a simple barrel connector any day.

sidebar: I'll admit to using damn near every wire termination known to modern man in my car. There are Molex Mini-Fits, Amp Mod-IVs, Molex 062s, D-sub connectors, Weatherpaks, I think I've even got an SVHS connector somewhere in the center console. And yes, I have used barrel connectors and vampire taps in several places as well. But I do own a proper ratcheting crimper for the barrel connectors, and I don't use them in places where they're likely to get wet.

I'd agree that there are likely no solder joints in a harness. However, two thoughts, wiring harnesses are not typically firmly fixed to cause the stress that would break a solder joint within the run of a wire. Crimping of a wire in a factory harness is usually to join multiple wires (not join a wire mid run) and is faster to perform in a production environment than soldering.

OK I think this "solder joints are bad because of stress and vibration" is bullshit.

That shit just will not happen unless you make a crappy cold solder joint. Worst thing I can think of is that the wire could flex repeatedly right at the joint and break. But that could happen with a crimp as well. Shrinkwrap over a joint should be able to function as passible cable strain relief.

Thanks for the shielded cable tip Joe. For those I'll use twisted pair with a sheath. I have several hundred feet of Canare star quad actually. That would be overkill though.

It can happen, but I think the magnitude of the problem is vastly overblown. I wouldn't solder an electrical connection going to a device that rotates through 90° of arc several times a minute and is expected to last for 10 years, but for the majority of automotive applications, it seems to work just fine. The wires going to my crank position sensor are soldered and shrunk, and they seem to be holding up nicely.


That's exactly where the breakage can occur (at the point where the solder first meets the wire) and like yourself, I find that a layer or two of heatshrink works wonderfully as a strain relief.


Wow. Yeah, star-quad is probably a bit much. Actually I can think of relatively few cables which I detest more than that stuff, particularly the L-4E6S version with the dense, cross-braided shield. Great specs and all, but really, REALLY time consuming to prep and solder XLRs onto, especially if you've got a dozen ends sitting in front of you needing to be terminated. Dare I ask why you have a bunch of it lying around?

I actually use a fair amount of Belden 9451 and 1504A in my car. Great stuff for MAP sensors, VR sensors, etc.

I actually have the L-4E6AT which just has a foil sheath and stranded ground around the outside. About 100% easier to prep than the cross braid stuff.

http://www.canare.com/ProductItemContentImages/369.jpg

It's all from several studios and live rigs I've wired. Also mic cables, instrument cables etc.

FaeFlora I might actually be making my own harness very very soon. I will make sure I document it for you.

What connectors are you thinking about using?

These look promising:

Molex sealed connectors

I was going to use all the stock connectors. More or less remove what I did not need from my stock 95 harness and then add in the extra things I have added. It could either go very well or horribly wrong.

Huh, never realized you were in the business too. I spend most of my time doing studios for radio stations.

And, honestly, we use very little shielded wire these days. Probably 99% of the cable that we run is CAT5. We use 25pair CAT5 trunks for inter-room (block to block) cabling, and within a studio or inside a rack, we have a custom single-pair jacketed stranded CAT5 that we use. We still use shielded cable for mics (though just plain ole' Belden 9451- no need for fanciness in stationary applications) along with the odd piece of hardware that actually requires a drain wire.

I have a complete 2004 Mazdaspeed Miata Wiring Harness! $300 Shipped to you via UPS ground? Very heavy, and the box is about the size a 19" TV.

To be fair, a layer of heatshrink over a good barrel crimp accomplishes the same thing, and is easier to accomplish in many places on the car where the space to solder is minimal. I've seen as many people solder poorly as I have seen bad barrel connections fail.

That said, I've got the ratcheting crimper with the multi-point crimps and a bunch of GM style connectors that I use for most of my stuff.