wallyman

Debating a complete rewire of the entire car (92 with PW, PM, Cruise and AC) as part of the LS swap.

I want to do a wire tuck of the engine bay, and move that fuse block elsewhere as well as generally fix 25 years of hack-n-splice on the car. My Dash is brutally hacked up (most of it my doing!), and the lights have been modified over the years too. I have a long list of electrical tweaks that I like to have on my cars and that is part of it as well:

Fog/driving lights via relay
USB charging ports
relocated cig lighter under seat
Glove box light & switch
Trunk light & switch & car show bypass switch
Stereo, speakers, Amps
Alarm, remote start
Side markers rewired to be marker and turn
Manual cooling fan override
etc.etc.etc.

I added most of that to my 94, and while doable as addons it is just so much nicer to just do it clean from the start and have things fused at the block like they should be individually.

So, first questions is: Has anyone attempted this? If so, post up some details. I'm thinking starting with something like the american Autowire kit or Painless Kit (I used an AAW stocker upgrade on my 69 Mustang over the winter and it was pretty nice to work with - but it had all the factory connectors for that car which I don't have for the Miata).

Second question is: If not, anyone have leads on the body wiring system connectors? I haven't dug into them specifically, but I am well familiar with Mouser & Eastern Beaver for some one-off stuff (ignition 6 way for example). Specifically I am wondering if anyone has a list of replacement connector part numbers...

I have thought about just rewiring the backbone wires, and putting in large multi-pin units at key locations (like a 20 pin at the front for all the front lights, and another at the rear for all the rear lights) and just reuse the last 3 feet of every stock one.. I really would like to replace it all though, to the very connector, to completely eliminate any historical gremlins.

Wallyman

acedeuce802

My roommate re-wired everything from his dash forward on his '92. He spent probably 2 months working on it, and I would still not call it acceptable. His mediocre wiring methods and lack of strain relief makes it less reliable than how it was before.

I don't have the information about the connectors and whatnot, because I'll be using my factory wiring behind the dash, but I will say that make sure you conform to proper wiring technique. I have around 30 hours into my engine harness alone, and still haven't terminated the ECU connector.

https://www.rbracing-rsr.com/wiring_ecu.html

I use this article to understand what top of the line wiring means, and then use past experiences and such to decide how close to this I need to come. But it's good to understand why the pro's do it this way to know what good techniques should be used in a passenger car.

wallyman

GREAT link! Thank you for that. That is perhaps the most impressive thing on wiring I have ever seen.. wow.

I'm not too worried about the "how" but rather they parts involved specifically. Rewiring the car is not overly difficult as long as you plan it well, but finding the right materials (especially proper Mazda connectors) is my worry.

SupaDupaSteve

I think you'll have a hard time finding all the connectors without just using a donor harness. Why not just get a clean donor harness and go from there? Rewiring the car would be a very long and difficult process. I completely eliminated the engine, AC, evap, etc from my factory harness and moved the fuse box inside the car. If you'll check out the last page of my build log you can see what I did. Also, I know itsallrigged used a kit to rewire his entire car.

wallyman

Hard time is my worry.

I have 2+ donor harnesses, but was hoping to just use new connectors.

I'll look at your build and itsallrigged too, thanks for the leads to follow..

mrmustang

Painless/Autowire kit is the way to go. Rip it all out and start from scratch.

wallyman

Except where do I get all the Mazda body connectors??? That's the issue. If I am just going to hack off 25 connectors from my stock harness and splice them on to the ends of a Painless/AAW harness, well, I just added 25 x # of conductor splices. Not making it better, making it worse. If I am going to rewire, I want factory crimp end conecetors I can put on the wires.

I spent a bit of my evening pouring over the 92 FSM diagrams, and my fuse blocks. The underhood one I want to move has:

30A Headlights (the bulbs)
30A Headlight motors
30A Engine BAT
80A Main Fuse
40A feeding interior fuse block
30A Main Fan (will be handled by the ECU harness)
20A Secondary Fan (also by ECU harness)
60A ABS (not used for me)
10A Airbag (not used for me)
10A Starter Signal (unsure but I think handled by the ECU harness)
Fuel Injector relay (handled by ECU harness)
Cooling fan relay (handled by ECU harness)

So really, I need to deal with the main fuse plus 4 more (maybe 5) and of those the headlights are really the only ones that belong out front. The ECU will be in the cabin so the fuses can be too. I think perhaps I have found something to work but I want to investigate more before I post it up.. looks slick on the surface but so does a lot of stuff.

The interior fuse block I have (the original) has a bunch of open slots which I think I can retrofit some feeds to and use.. I also have a 94 fuse block out of a parts car I need to look at. I need to investigate if I can just add feeds in and out of it, that may be the ticket.

I love the idea of a complete rewire, but the reality I think is that there is no elegant solution. The AAW kit for my 69 Mustang had every single factory connector included, you weren't salvaging any old connectors bodies or anything. That is what made it sweet, ever piece was brand new. Just changing the feed wires but leaving all the old connectors (and adding in a tons of splice points) really doesn't appeal.

I'll continue ferreting out what I found and keep at it. If nothing else I may have a solution for the underhood box.

wallyman

Ok.. so the stock NA Miata fuse block in my 92 isn't fully populated. It looks like this one:



Note the empty spots? They are empty fuse holders without wiring. If only we had terminals...

...like THESE!



Fuse Block Terminal - 1-Way

$0.36 each at the time of this post.

Part number is 7388520 @ DelCity. Called "Single Terminal for 1 Way ATC®/ATO® Fuse Block".

Pretty sure that allows us to utilize the remaining 6 fuse spots. Going to order up a handful and see but having extracted a stock on it looks identical minus some 'wings' which I think are used for orientation of the terminal.

so i think this solves my interior cabin needs (USB ports, lights, etc). I still need to solve the underhood part which is in process....

wallyman

Additional detail:

The Mazda one has a hole in it right where the "15" is on the picture.. the hole is how it locks into the housing. So it's 99% right, and I'm thinking some minor surgery with a tiny drill bit will solve that issue.

Also, found TE & Delphi info from a Land Rover forum.. additional options:

TE (AMP) part number - 880397-2 - For 0.5 – 1.5 mm˛ cable
TE (AMP) part number - 880399-2 - For 2.5 – 6.0 mm˛ cable
TE (AMP) part number - 880398-2 - For 1.0 – 2.5 mm˛ cable

Delphi part number - 12147656 - to suit 1.5 – 2.5 mm˛ cable
Delphi part number - 15344731 - to suit 0.5 – 1.0 mm˛ cable

Terminal Supply Company part number 12020334 - 20-18AWG, 10A
Terminal Supply Company part number 12020321 - 16-14AWG, 20A
Terminal Supply Company part number 12020400 - 12-10AWG, 30A

I haven't tried any of these (yet) but they look promising. I may order up from DelCity and Mouser to try them out.

wallyman

Ordered up the TE and the DelCity stuff.. will report back how they work.

charchri4

Well speaking a the worlds messiest under hood car I would say it is a hell of a lot of work for zero gain. However I get the appeal and those who do it well create true art in their cars.

I agree with Dave and would not start from scratch but with a donor harness.

wallyman

I've got a couple.. mostly complete 90 base car (no AC/PM/PW) and a decent 94 harness (PW/AC/PM) plus scraps from another harness. Working on the stuff I still need to retain and where to locate relays and fuses.. more to follow.

wallyman

They arrived, and test fitting is done! Shown on a 1/4" grid paper. Here ya go:



If you make these modifications, they fit more snug than stock ones:



Ignore the bottom part of the mod photo, if you solder or crimp the terminals on, those two would be around the wire insulation anyhow. I only bent them up to test fit.