I cut all the way through my engine bay harness with a cutoff wheel.

[Lej]

I'm looking to relocate my 2 engine bay fuse/relay boxes into the cabin somewhere (or possibly inside) of the glove box compartment. I made one huge cut in the middle of the harness at the front of the car (inbetween the head lights) and 2 more cuts to free the fuse boxes from their jail of the engine bay.

I brought the whole loom inside the cabin where I was going to begin the process of soldering/shrink tubing and rewrapping the harness, but I ran into the issue of some of the wires being DUPLICATES. For example - After my cut, one side of the cut may have THREE all pink wires, with the same number of hash marks. Or an all black wire with a red stripe. TWICE. ...... Now SOME of them are different gauges, so I can match them up, but the others - I'm clueless. I realize I could trace them down to the interior kick panel fuse box, and see where they go and try to use an ohm meter and figure it all out.,,

Does anyone have any diagrams that could help with this? Or a little insight on it?

http://i.imgur.com/H8u5A12.jpg

http://i.imgur.com/8bziCWt.png

[zombiewolf513]

Start with the obvious ones, the multiples run back and forth, so for those you could likely find in the FSM diagrams, but you'll probably have to trace some anyway to see where they go.

[roboticnissan]

sweet jesus all that stuff unplugs and comes throught the fire wall then you just plug it all back in under the dash!!!!

[andisan]

Wow that was ballsy, I would of labeled all the wires before cutting them, with at least numbers

[KAT-PWR]

HAHAHAHA
Damn sorry but if that was your best idea for beginning to tackle this project buy a new harness. Strip it outside of the car, delete what you don't need re-loom it and send all the shit where you want it to go.
Did you not even google "S13 fusebox relocation/tuck" before deciding chopping your wiring harness into pieces was the best solution?
https://rdelaneyjr.files.wordpress.com/2014/09/mind-blown-jackie-chan.jpg?w=500
I must be a white girl cause i can't even right now.

[kruked]

Oh em gee!!

[e1_griego]

You're not alone: http://zilvia.net/f/showthread.php?t=593678

[rawgarage]

I have a harness you can buy.... Text me 9792366891

[CrazyTrance]

Oh my fuckinggod. hit up that guy^^^^

Lmao

[Mofuhcka]

Stupid is as stupid does

[MilkMan1218]

I am the person who owns the car, and yes hindsight I should have labeled the wires. I also know that with no auto knowledge I rebuilt my rb20 from nuts and bolts and it runs beautifully. I'm sure I can fix this up, it'll just take longer than usual. But hey, the least I can say is I've definitely learned of better ways to do this. Those who say I need a new harness are afraid of challenges, I live for them.

[zombiewolf513]

Working with a fresh harness is a challenge in itself.

Took me about 6 weeks to rewire the whole car right without pulling my hair out by working on it non-stop

Document and label EVERYTHING

[KAT-PWR]

I am the person who owns the car, and yes hindsight I should have labeled the wires. I also know that with no auto knowledge I rebuilt my rb20 from nuts and bolts and it runs beautifully. I'm sure I can fix this up, it'll just take longer than usual. But hey, the least I can say is I've definitely learned of better ways to do this. Those who say I need a new harness are afraid of challenges, I live for them.
:picardfp:

No we just understand the valuation of time. If you value your time at say any price above $1 you would quickly understand that buying a new harness is the better route. Plus after you solder all of those connections back together which you said the harness is in 3 or 4 sections?.... times the number of wires in the harness which i just going to guess is over 50? So 200 or so amateurly done solder joints that will probably break as you man handle everything to where it needs to go. So even if by some magical stroke of luck that you accurately mapped the ENTIRE harness for the car it still probably wont work... And if we take the more likely scenario that you did not dead on nail the schematic across 3-4 bridges you fry stuff.
Anyone that can read and has a set of tools can put an engine together and have it run if its been machined properly and no corners were cut. I've done it, many have. But wiring on this scale is a whole nother animal. IMO more complex than building an engine.

[andisan]

I'm sure it would be easier to just buy a whole new harness, there is a lot of people selling them anyways, body and engine

[Johny5]

Kyskyskyskys

[KiLLeR2001]

This type of wiring job is for expert level 100. Since you decided to cut the harness in this manner, you are clearly at level 1.

[s14gmo]

Work smarter not harder! Just buy a new harness and go from there. Goodluck!

[MilkMan1218]

Well there are only 26 ish wires that are duplicates. After tracking them down they are mostly lights, signals, windows, windshield wipers, stuff like that. As for amateur soldering and man handling, it's pretty simple to solder a good connection, especially since it's basically welding with wires. As for the man handling, that won't be necessary since the dash and support bar is off. I'm not some barbarian going in slinging piles of solder on two coils and just throwing stuff around. Finally, it's not like I cut into the engine harness, it's a race car all I need are lights and a motor.

[kunt_masha]

Prp Tip: You can unplug and push the harness through the firewall in 30 minutes..

[LockOn!]

1. Throw in garbage
2. Replace with new harness the right way.


No way in hell you are going to get all the wires together correctly. Even if you do, every connection is another chance for failure in the future. Unless your a literal pro at soldering and sealing connections, this will fail.


it's a race car all I need are lights and a motor.

This is the exact attitude that is ruining these cars and the reason the "doing it wrong" thread is a thing.

[kruked]

Prp Tip: You can unplug and push the harness through the firewall in 30 minutes..

This was already mentioned in post #3 if you would've read all of the post.

VV

sweet jesus all that stuff unplugs and comes throught the fire wall then you just plug it all back in under the dash!!!!



No way in hell you are going to get all the wires together correctly. Even if you do, every connection is another chance for failure in the future. Unless your a literal pro at soldering and sealing connections, this will fail.

It can be fixed, maybe not by him, but it can be done.

[slow40sx]

yeah, definitely get a new harness, and in the future I would recommend searching before you touch anything, also maybe glance at it all before you start cutting things, the fuse boxes aren't in any jails, they are held in with bolts and they fit through the large cut outs in the bay and there is a large plug under the driver side that bolts together the front half of the car harness to the back half, a quick visual inspection could have told you that especially with the dash out of the car, so I would 100% get a new harness and go from there

[Lej]

Hey guys, it's OP. So yeah, posted this for Milkman (the owner) .. I told him there was for sure a better way... seeing as the factory didn't have to reattach it in the middle to get it in there in the first place. And the fact that FULL uncut engine bay harnesses are for sale on Ebay.

I knew it was a stupid idea, BUT - my one question is ... How do you pull that white box through the firewall? (The one that is originally on the driver side in the kick panel attached to the fuse box.) Does it go through the side of the car and AROUND the firewall? Or is there actually a hole to pull it through?..

Pic for reference:

http://i.ebayimg.com/00/s/OTAwWDE2MDA=/z/lrkAAOSwWnFV~akc/$_57.JPG

[zombiewolf513]

The SMJ goes out by the left wheel. it fits. it fits.

[Lej]

The SMJ goes out by the left wheel. it fits. it fits.

Cool - that makes good sense. Wish he would of done it that way! haha.

[Biggamehit]

Wow.....

Sent from my 402SH using Tapatalk

[gostrider]

I have one for sale 80$

[AzS13hatch]

I highly suggest not using solder on your harness. That is one of the worst things you can do in this situation if you plan on still using your cut up harness. Use non-insulated butt connectors and heat shrink over them. It is easier and much more reliable and long lasting.

Just for reference, this is what I'm talking about

http://www.maneywire.com/butt-connectors-insulated-seamless-p-1462-l-en.html

[Cpreston]

I highly suggest not using solder on your harness. That is one of the worst things you can do in this situation if you plan on still using your cut up harness. Use non-insulated butt connectors and heat shrink over them. It is easier and much more reliable and long lasting.

Just for reference, this is what I'm talking about

http://www.maneywire.com/butt-connectors-insulated-seamless-p-1462-l-en.html

That is misinformation big time. Absolutely nothing wrong with soldering your harness if you know what you're doing, and is in fact better than butt connectors.

Anyway, I recently had this same problem except I cut my engine bay harness in the driver side fender to relocate it into the engine bay. Like you, I just cut the harness assuming all the wires would be unique in one way or another (size, color, striped, dotted, etc.) and as you found out, they're not.

I labeled all the ones that were unique with numbers and letters. Doesn't matter what you label them as long as you label the corresponding wire the same.

For the rest of the wires, I looked at my service manual and located all of the connectors on one end of my harness and knew that all of those wires had to go to those connectors. So I would start hunting the wires, say I started with the pink wires, I just looked for pink wires going into connectors at that end of the wiring harness. Once I found what connector and pin the wire went, I looked through the wiring diagrams in my fsm for ones with that connector and that pin. Once I found the wire on the wiring diagram I obviously was able to see what the wire went to. Say I found the wire that went to the headlight motor, I would label that wire then go to the headlight motor, find the wire and then find the other end of it with my multimeter.

And for all the wires that are duplicates, you have to find all but the last one. If you have two Orange wires and you find out what one does, you don't need to know what the other one does because it'll be the only orange wire left.

Hope I didn't word that too confusing. And if you decided to buy a new harness instead I do not blame you at all but I'll leave this comment anyway incase someone else makes the same mistake

[AzS13hatch]

Read this
http://www.speedhunters.com/2015/09/knowledge-boost-tackling-your-wiring-nightmare-part-1/

I'm not an expert on wiring but I have done quite a bit of it. Feel free to take my word and let it go in one ear and out the other, I really don't mind. Just trying to give the advice from professionals as I have read it and comes from a highly trusted source. I started using solder a long time ago but have moved on to the connectors as they are much easier to work with and then I saw this article and was happy I did when making my chassis harness.

[EnnEssEnnKAT]

Work smarter, not harder. Definitely should have labeled them and now it's not going to be easy at all and there will be problems..

[KAT-PWR]

That is misinformation big time. Absolutely nothing wrong with soldering your harness if you know what you're doing, and is in fact better than butt connectors.
Don't be foolish now.
Does solder work? Yes.
Is it better than proper metal crimps? No.
OEM manufacturers use crimp connections, they are less effected by external factors.
You said butt connectors so thats a bit vague.

[Cpreston]

Don't be foolish now.
Does solder work? Yes.
Is it better than proper metal crimps? No.
OEM manufacturers use crimp connections, they are less effected by external factors.
You said butt connectors so thats a bit vague.

There is a time and place for each. No I don't think butt connectors are a bad idea, but they're also not the best for every situation. The only real advantage of a butt connector over a properly soldered joint is the time it takes and how easy it is.

I have never once had a properly soldered wire become a problem at all.
What are the external factors you're specifically talking about?

Also, I'm not sure this is true but I have heard that a butt connector is more likely to change the resistance of the wire.

[shawn1331]

There is a time and place for each. No I don't think butt connectors are a bad idea, but they're also not the best for every situation. The only real advantage of a butt connector over a properly soldered joint is the time it takes and how easy it is.

I have never once had a properly soldered wire become a problem at all.
What are the external factors you're specifically talking about?

Also, I'm not sure this is true but I have heard that a butt connector is more likely to change the resistance of the wire.


I do ALOT of wiring in my trade and I can tell you a butt connector is the superior method of wiring for a cars harness as compared to soldering. The main reason solder kinda sucks in car wiring is because the harness moves and has the possibility to break the connection. Albeit very rare it has been known to happen. As long as you crimp properly the wire will never come out nor will it break and they are also better insulated from the elements (water,salt etc.)

With that said, my entire sr20 harness in my car was soldered by me, then hot glued and insulated and taped because I didn't have any crimp connectors at the time. It's been working fine for 2 years with 0 wiring issues.

So I really don't think it's a big deal, if you have crimp connectors or access to them use them, but I wouldn't feel weary of soldering AS LONG AS you know what you're doing while soldering.

Fun fact: Solder creates more resistance in a wire, especially the more you use (obviously)

[KiLLeR2001]

Been wiring for around 8 years now. I use to be die-hard on the soldering, then I started looking at OEM harnesses and how they are done. Now I'll use butt connectors/crimping w/ adhesive-lined heat shrink 90% of the time. The other 10% of the time I'll use solder.

[Cpreston]

I do ALOT of wiring in my trade and I can tell you a butt connector is the superior method of wiring for a cars harness as compared to soldering. The main reason solder kinda sucks in car wiring is because the harness moves and has the possibility to break the connection. Albeit very rare it has been known to happen. As long as you crimp properly the wire will never come out nor will it break and they are also better insulated from the elements (water,salt etc.)

With that said, my entire sr20 harness in my car was soldered by me, then hot glued and insulated and taped because I didn't have any crimp connectors at the time. It's been working fine for 2 years with 0 wiring issues.

So I really don't think it's a big deal, if you have crimp connectors or access to them use them, but I wouldn't feel weary of soldering AS LONG AS you know what you're doing while soldering.

Fun fact: Solder creates more resistance in a wire, especially the more you use (obviously)

Yeah I shouldn't have said solder is better than butt connectors, Becuase they each have their own advantages. Personally I prefer to solder small wires and crimp large wires. I think what it comes down to both ways being completely acceptable if done properly.

But I'm the same way as you, I've soldered countless amounts of wires and have yet to have one fail for any reason. So I guess I'm just biased to solder because of my experiences. I have barely ever used butt connectors but I will probably look into them next time I do some wiring.

[AzS13hatch]

^^ +1 on the adhesive-lined heat shrink, that stuff is awesome!

[Sills]

Even with a diagram youll have problems figuring out which is which as they are still the same color no matter what. Jdm Legion has good wiring diagrams that I used for my S14 Silvia's Rb swap.