2nd Gen Wiring Overhaul - A slow descent into madness

I think the 1/0 should be thick enough? That's also what I'm thinking to run between the battery and bus.

 

1/0 should be fine. I went with 2/0 just cause I could and tend to overbuild my wiring. Can’t remember how long my wire run ended up being to the truck bed. Somewhere around 15 ft or so, but I could’ve gotten away with 1/0.

 

Hi all, new to the forum and, my new to me 2008 2.7l 5spd.

So the alt is shot (along with ac compressor and a few other things as it has sat for approx 4 years)

So saw a 200a alt which I'm probably getting and was wondering a) does op sell a big 3 kit or did he post the lengths and I still can't see them in the thread and b) anyone do a 2.7l upgrade and what difference where there in gauge and lengths.

Reason for wanting to upgrade is I'm probably putting a sound system in and also I will be mounting an old fisher MM1 plow. So the need is real.

Anyway thanks in advance for any help. (BTW I have looked through a few posts before I wrote this, but was not seeing 2.7l upgrades)

 

I very much doubt the lengths for the 1GR will drop right in to the 4cyl plant. Your best bet, if the truck is going to be down anyway, is going to be do what I did - get estimated lengths of the factory runs in-place, then dry fit half-completed replacements for final length.

 

@deanosaurus , thanks for the (very) prompt reply. I did see the picture but completely missed you had added lengths in (doh!). I understand about the 4cyl probably being different but, hey, you dont ask you'll never know. Someone may say oh yes use...... So again thanks for the response and I will probably get the car running and then on my own time have a play with the estimated length etc. If I do get this done I will try and post the lengths to help the next 2.7l person.

 

The time has finally come to clean up and consolidate the mod wiring.

I'm going to be dropping in some new lights soon, and as I was pondering how best to run them, I realized that I had a lot of onesies and twosies snaked wherever was convenient, and that adding more to it would have pushed me dangerously close to rat's nest territory, even with military terminals.

I agonized over how to do it for a while and settled on the passenger side fender. Since this is a TRDOR that space was clear from the factory, and was only hosting my winch controller like so. I figured with a little bit of planning, I could mount an aux panel, bus bar, and the winch box all on that fender.

Here's the (almost) finished product first:



My in cab control panel (seen in this post) currently has a winch arming switch (12v cutout) with LED "armed" indicator, and a dpdt momentary for winch in/out. This winch control circuit is fed 12v by the winch via the control box. I want to keep the winch controls independent of the other three switches on the cab control panel, so I can disconnect the winch at the battery and maintain function of the remaining accessories. So, the 3 pairs for the in-cab relay switches will be joined by an independent +12v fed from the bus bar.

The bus bar will be fed by 4AWG runs directly from the battery+ and battery-, run along the top of the firewall. This is way the hell more than big enough for the devices that will be in this circuit but I have it (and the appropriate lugs) on hand, and it looks hella cool to have big wires.

The six relays in the new aux panel will be powering a DD 18" lightbar, a pair of DD flush mounts (amber backlights linked to fogs, white floods linked to light bar), the relays for my Headlight Services harness, and the horn, with two empties ready for future dumbass stuff (probably chase lights and an ice cream truck PA).

I thought about going with a Bussman setup but ultimately wanted to be able to use IceCube/Bosch-style relays because they're easier to source in a pinch and I have a pile of good Densos scavenged from the fusebox used for testing earlier in the thread.



So, I picked up some 1/4" hdpe stock (cutting board, Ocean State Job Lot, $5) to mount everything to and got the routing and layout figured out. It's shown mirrored here, just because of how I traced everything on cardboard to fit the mounting plate. The next seven shots are a time lapse of me painstakingly populating the relay box with 12AWG tinned copper for everything except the signal wires, which get 22AWG:













And here's the mounting panel rough cut and with the aux panel and busbar tentatively positioned, so I can dry-fit everything and figure out how, exactly, I'm going to mount it in the engine bay:





When I chopped up the Headlight Services harness, I thought I would be able to basically completely re-use/preserve it. I ended up being just scant inches short of where the leads needed to go - basically, I forgot to account for the new mounting position being farther back than the original/manufacturer's intended configuration.

After several days of wrestling with wiring, I needed a little bit of a mental break, so I decided to experiment with splicing techniques:







After that little interlude, I got the DTP connectors put on the relay outputs, tidied up the underside wiring, and labeled everything:



Here it is after several rounds of wrestling/marking/trimming, in its final mounting position. What I ended up doing was using one of the M8 threaded holes on the fender towards the firewall (mirrored from the threaded holes where the stock fender ground attaches on the driver's side), and the washer fluid tank mount hole. There's a 30mm HDPE spacer on the rear of the panel, and I used a stainless "Z" type bracket from the spare parts bin for the front.:



There are a couple of skipped steps here. You'll notice the painstaking cable management, and also that the Headlight Services harness has been carefully spliced. I used Ancor Marine 12/3 for the powered runs, and 16AWG marine wire for the input plug (the one that connects to a stock headlight plug to signal the relays).

I ended up using DTP 4 pin connectors with one pin blocked off to turn the old Headlight Services harness into pigtails that plug into the new aux harness (DT 3 pin for the 'input' plug).

If you're not super familiar with the DT style connectors, pay attention to whether you need DT or DTP based on the wire gauge and amperage of whatever you're trying to be fancy with. If you're using 10-12 AWG you will need to use DTP connectors regardless - the larger pins will not fin in the DT shells.



Here are a couple shots of everything installed. The winch controller fits nicely. I ended up using a clip-on boot from the factory starter wiring to wrangle the winch control cable and winch control ground; when I finish running the new in-cab control bundle (multicolored bundle currently seen tucked behind the mounting panel) I'll get detail shots of that as well as the DT/DTP connectors.

You can also see in this next pic where I ran the 4AWG pair along the existing bundle on the back of the firewall.





Overall I'm happy with it, but there are a few things I want to change next time I dig into it (which will be when my 3d printed switch panel arrives and I populate it).

1) I want to replace the all-zipties loom job behind the mounting panel with some brackets made of HDPE offcuts,

2) I want to change the way the bus bar is mounted,

3) I don't distrust the silicone plugs on the back of the aux panel, but I would feel better about it if I put down some RTV - I'm thinking a thin, continuous layer of it applied to the entire back face of the aux panel,

4) I want to loom up that Ancor 12/3 with some factory style ribbed black loom. I thought I had some that would fit, but did not,

5) I want to bevel the mounting panel for a more finished look, and possibly throw on some black trim on the bottom edge to fill the gap between the bottom of the panel and the top of the fender curve.

 

Buddy of mine who is big into 3D printing visited a little while ago and offered to make me a switch housing to replace the janky folded thermoplastic. Here's the pile of test prints, design thoughts, curve gauges, and an initial prototype:


Here's the switches moved over to the proto. Not shown is the cleanup inside - I replaced a lot of wire loops with ring terminals, used some better wire, and generally did a much less temporary/"just to make sure it works" job:


Here's the housing placed after slightly enlarging the hole in the head unit bezel and drilling one in the housing. Not pictured is replacing the uninsulated spade terminals wrapped in shrinkydink with fully insulated spade terminals. The new control wiring from the relay box was also run, and the winch and relay wiring inside the dash was loomed together neatly:


I also loomed up the new wiring under the hood, I'll snap some pics of that when I get back in there in a day or two.

Here's the prototype panel installed and working:


You can see in this next shot that we forgot to account for the slope of the top of the head unit bezel, so it tilts a little awkwardly:


I took some measurements to alter the geometry of the bottom surface of the housing with the next iteration (to compensate for the slope of the bezel), but the interior geometry and switch placement geometry is spot on.

We also discussed a super trick backlit faceplate idea that he's going to mess with for the next iteration.

Even though it's not perfect for the time being, it sure as Hell beats what was there before.

 

About to put an Evo 10 in my ARB. Did you have to clock the winch connection side or handle side at all?

 

This has big "Too close for missiles, switching to guns" vibes.

 

Yes, I had to clock it - not difficult at all, the directions in the box are pretty good. Don't forget an offset fairlead if you're using synthetic rope, and make sure to use good bolts - I used the galv crap that came with Warn's offset and they snapped under a pretty modest lateral load and the line twanged against the edge of the opening in the bumper and snapped. Save yourself the hassle and put in some Grade 8/10.9s from the beginning.

Yeah, exactly.

 

Why do I feel like my harness has more wiring coming out of it? We saw one that looks like it was running through the harness then up and under the manifold.

Did everyone just unbolt the bracket (2 bolts, right?) then pull it out? What else was disconnected other than the alternator and starter? Do I see a small connector on the left end of that main harness?

I think it was this guy right to the left of the new alternator wire.

 

So is the one crimped terminal that's 90° a 1/0ga, or is it better to just go ahead and get another 90° 4ga for the alt+ that goes into the fuse box? Thanks and I look forward to getting this done here very soon.

 

Edit: The alternator to fusebox run, a 1/0 cable, uses a bent lug.


Also, don't order bent lugs, they don't seem to necessarily be the same thing as a bent flat lug, if that makes sense - I found that the better fit was just cranking a flat one in the bench vise, it left a "deeper" 90 that fit the contour of the fusebox much better, I tried a factory 90 lug first and it was going to need clearancing of the fusebox body.

 

Thank you for clearing that up, and for the advice on bending an otherwise flat terminal to 90° vs purchasing a prebent terminal... pics and all are much appreciated.

 

I have a dedicated thread for the Big 3 portion with more discussion and I think more photos that may be helpful - https://www.tacomaworld.com/threads...l-v6-get-ready-for-spring-maintenance.734046/ Do note that I no longer sell the kits.

 

Hey man, something was bugging me about this so I took a more careful look - it is indeed the Alternator -> Fusebox 1/0 cable that requires a bent lug. I have edited previous replies/notes for clarity for others in the future.

Again, the Alternator +12v feed to the fusebox requires a bent 1/0 x 5/16 lug, which may also require minor fitting with a round file to seat properly. The bend is also not quite exactly 90 degrees, and do be mindful of the crimp orientation to achieve a good fit.

 

The small one-pin connector at the L/H end of the harness shown,
is to control the starter solenoid. This wire routes up through the
harness, alongside the block and starter grounds and the
starter's power cable, and joins up with the 3 other small gauge
wires coming off of the green plug on the alternator (along with
the alternator cable). These 4 wires then terminate at the white
4-pin plug that connects inside the top of the fuse box.

BTW, If anyone needs the wire harness support bracket,
bolted to the side of the alternator,
the part number is 82715-04130.
This is the metal bracket shown in previous posts #4 and #12.
Mine was severely corroded and the two tabs for the plastic
wire raceway were rotted off

This was a great Thread!
I ended up going with the harness kit from JeepCables.com
as mentioned by Naveronski on post #77

 

@deanosaurus I've been considering doing the Big 3 update. I have the 4 cylinder, 2TR-FE, motor. Is the process the same with the 4 cyl vs 6 cyl?

 

Conceptually, yes, but the location of the alternator is different. You won't be able to use the wire lengths for the 6 cyl, you'll have to figure them out yourself. You can use something like a piece of rubber hose to mock up each run and get an idea of the length, just cut your wire roughs long so you have room for error. Terminate one end of the rough cut wire, run it, mark it, remove it, cut and terminate the other end, then reinstall.

If you do go through with it, please post up your lengths - I did a one-off for a member here who gave me some lengths off his truck, but I never heard back if they worked or not.