Help in getting started on a wire harness

[rb70383]

How do those that have built your own wire harness get started? I tried to make a diagram but I wouldnt be able to read it afterwards. I even tried to modify a factory one to add what I have added and it didnt turn out so good either. Anyone offer any ideas?

I have some GM fuseboxes that I am going to use. Getting new connectors/pins and using fuses to replace all the fusible links. Installing relays to lighten the load on the dash switches. Just all your basic upgrades. How do some of you get started on a project like this. I guess I need that small intial shove out of the airplane.

Would hate to think I finished and find out I forgot a couple vital circuits.

[astroracer]

I have the harness for the van mostly figured out. I picked up a couple of how to books from Tony Candela and used an electrical manual for the van to figure out all of the wires. Get a manual for the car "?" you are wiring and go from there.
Here is a link to a post in my build thread. Look thru the thread a bit. You will find an excellant source for wire in the "Wirebarn" and using the internet to find wiring diagrams is very easy.
https://www.pro-touring.com/editpost.php?do=editpost&postid=934767
Any questions just ask.
Mark

[ChevelleNV]

the first harness i did was started by taking an existing harness form another car and modifying it for my needs and application.

[FlyDoc]

1st you must decide on conventional positive activated, full voltage, low voltage, or ground activated circuits. Then you need to understand how each type of switch works.
and this is the key to making your system work
ONE CIRCUIT AT A TIME,ONE WIRE AT TIME!!
don't try to plan the system at once it will be overwhelming, and cause headaches!
my plan is to use a low voltage or ground activated. this will reduce overall weight of the system by not having large wires to the switch then to component.
and use the references that Astroracer mentioned.
if you need any help just pm me. wiring is one of those things I like doing!

[dadmoonbunny]

Flydoc,

New user here. Please forgive, but I have one question.

Can you direct me to a source that will help me...I have a 2004 Dodge Neon, that I want to get rid of the computer, and most of the wiring that surrounds it in function, and go with a more conventional harness that I can actually work on.

[astroracer]

Flydoc,

New user here. Please forgive, but I have one question.

Can you direct me to a source that will help me...I have a 2004 Dodge Neon, that I want to get rid of the computer, and most of the wiring that surrounds it in function, and go with a more conventional harness that I can actually work on.

You should start a new thread.... Would get more initial hits then piggybacking on someone else's...

Get a wiring manual for your Neon. It's really that easy. If you can rewire a computer controlled car to function as it should without the computer I would think you should be able to work on an existing harness if you had the right tools...
Mark

[FlyDoc]

why reinvent the wheel?
fix the issues that are in the system now.
what is the issues?

[ehummelman]

I suggest drawing it out in major sections. When you break it down into engine, headlights/fans, dash, taillights, etc. it is much easier to understand what is going on and where things need to go. Once you have all your major circuit groups mapped out, you can run wire. I would start at the end point (bulb, sensor, choke, whatever) and go backwards to the fuse block. Also, since you're starting from scratch, use as many relays as you can, and use the heaviest, best quality grounds you can. And lots of them. Having good grounds is often underestimated. As is good connections, whether they are crimped, soldered, or both.

[Mr_Roboto]

Neon is interesting. Just a word of warning, some vehicles in the GM camp are run off the ECU that late in. I don't know if yours would be the same. Are you going to aftermarket gauges or sticking with OEM?

If you're not going to be using the Neon's engine harness what are the plans (aftermarket ECU, carb/Dizzy/MSD etc.) This will determine the changes you need made. It's a lot easier to tell you what you should be doing if we know what A and B are.

I see you mention Megasquirt in a thread or two, my advice is to get the breakout harness for it. Are you planning on running the stock engine or another engine? If a stock style engine (your harness would "bolt in") You may just want to knock the ECU connector off, get a pigtail for your Megasquirt (well worth the bucks, soldering the DB-37 is a pain) and just use the stuff you need for it. That's what I did on my van. Depending on how it's set up you can either leave the old stuff in place, clip it back to whatever bulk head connector you have or just pull it out of the harness. This would be your typical batch of emissions stuff and engine controls that aren't used. I have never set a Neon up before, but what's your full engine config going to be (injectors, ignition, sensors etc.) I may be able to provide some advice.

Besides this I'll say never just twist/tape stuff or use crimp connectors. Solder/heat shrink is the way to go. You won't end up with as many weird issues after.

[minendrews68]

I decided to jump in here also, but this might help the original owner of this thread. Where is a good place to buy all the connectors, fuse boxes etc?

Carl

[Red67Mustang]

Check out Caspers Electronics (link below). As the son of an Electrical Engineer I was raised to know there only one way to prepare wiring - the right way! As such, it was vital to use quality components; I wired my car using sealed Metripack connectors of varying sizes (based on the circuit amperage). Worked out great, and happy for it considering the 160 amp alternator and the electronics I have in this "vintage" car... plently of power on tap - could wreak havoc if not controlled.

As for the harness, I laid mine out in CAD (including wire color and gauge) and plotted the whole thing using the large format plotter at work (so I could read it) on a 3'x6' piece of paper... not practical but great for taking notes, making tweaks, etc.. as I wired it up. Strategically, I made a new harness (for everything I added; EFI, fans, gauges, etc...) to go parallel with the repro 'original' harness, and made connections between the two when needed to utilize factory circuits. I found this simpler and avoided the need to source all new factory style connectors. It's 100% new wire, no 46 year old wire!

www.casperselectronics.com