4.0 Wiring Clarification

[Nalanthi]

I'm hoping that I'm not repeating a topic that has more than likely already been asked, but...

I went through every tutorial I can find, and I'm totally clear with most of the under-hood wiring that doesn't already connect directly to the engine harness, etc., but am completely unclear on what to do with the big white plug.

I have both harnesses out and as I started to map them, I'm completely at a loss in determining what corresponds to what where the colors don't quite match up... or since I'm going from a 1990 BII 2.9 to a 1994 Exploder 4.0, is the BWP completely plug and play?

The Chilton manual doesn't directly cover this.

Again, please forgive if this has (more than likely) been asked - but I did not find anything via searching.

Edit: I guess what I'm asking is - where could I find a link to the pinout of the BWP on each vehicle to verify what is what.

Edit 2: I think I understand now - after looking it over, the BII BWP is used, as the entire length of wires running from there along the front of the truck and back to the dist box is considered to be the headlight harness. The section that runs along the firewall is from the exploder and henceforth never feeds into the BWP?

 

[BabyBronco89]

You need to either get a 90 ranger 4.0 harness or get the entire dash harness out of the 94, the plugs won't quite match up
I just got done doing my 86 b2 2.9 with a 90 4.0l and harness and there was enough splicing there to give you a headache, or try finding a 91-92 explorer, that's the next easiest,

Oh and you don't have to worry about the harness being manual or auto, the auto ones are a lot easier to find in the junk yard,
And I believe the 94 has egr, so you will probably want to eliminate that, that's just more wiring and headaches


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[adsm08]

The need for a Ranger harness is actually not quite true. It just makes things easier.

A handful of wires will need to be added to the Explorer harness, all of them are for the rear lights. IIRC there are two wires that need to be relocated in the BWP for the Explorer harness, but other than that it is the same.

The biggest difference comes in the fact that the wiring for the rear lights runs inside the passenger compartment under the carpet on the Explorer, but the Rangers and BIIs had it running outside along the frame.

 

[Nalanthi]

The need for a Ranger harness is actually not quite true. It just makes things easier.

A handful of wires will need to be added to the Explorer harness, all of them are for the rear lights. IIRC there are two wires that need to be relocated in the BWP for the Explorer harness, but other than that it is the same.

The biggest difference comes in the fact that the wiring for the rear lights runs inside the passenger compartment under the carpet on the Explorer, but the Rangers and BIIs had it running outside along the frame.

Thanks for the response.
I believe that I was just being retarded - overwhelmed via overthinking.

What I get now mapping it out is that I can use the BII BWP and confine the majority of splices to the dist box/4.0 ecu harness, save a few elsewhere.

If I could locate a 90 harness, all the better... but finding a whole harness at the local upull that hasn't been cut into is damn near impossible IF I could actually locate a 90 4.0 Ranger. (especially since the 4.0 is in the bay and ready to be bolted to the tranny).

 

[Nalanthi]

I was trying my best not to rez this thread to ask more stupid questions, but... I had one or two more questions on wiring that I just couldn't put my finger on from some of the write-ups in the tech section.

The driver's side wiring seems pretty straightforward via the documentation (a few arrows are questionable), but I'll square that away when I get home from work today.

I have everything else working (exception of the engine) - lights outside and functions inside the cabin, but...

There are two wires from the 2.9HH that I'm unsure of - the y/bk and the bk/y that used to feed the EEC relay and the fuel pump relay. Do these need to be wired up to two of the spare fuses in the 4.0 dist box... or to the 4.0 relays?

Again, sorry for being retarded

 

[adsm08]

What is an "HH"?

 

[Nalanthi]

What is an "HH"?

HH - headlight harness @ the power dist box. I'm an idiot and in looking at it with a fresh set of eyes realizes that they need fused. I'm having a terrible time with these semi-complete Chilton diagrams.

 

[adsm08]

You should have taken the Explorer head light harness with the rest of the wiring. It would have plugged right into your bulbs with no mess and all your EEC wiring would be been consistent with your transplant parts.

 

[Nalanthi]

You should have taken the Explorer head light harness with the rest of the wiring. It would have plugged right into your bulbs with no mess and all your EEC wiring would be been consistent with your transplant parts.

Figured it out - the wires mentioned will be largely unused.
Here's the shitty part... was labeling the plugs from the bii HH for the driver's side splicing aand found that when I went to label the exp 4.0 plugs, low and behold it's a commiefornia engine. The amount of cussing that ensued...
'Least I have the ecu and fuel pump firing as needed, but the rest doesn't match up like in the diagram. I'm going to have to map that out.
Unless someone has a write-up for that, I may possibly have a tech article submission after I untangle the driver's side mess.

 

[adsm08]

All the 94 Explorers were up to Cali emissions. It's much more forgiving than an OBDII system would be though. I have a 94 Ex harness and 94 SEFI comupter in my truck on a 92 engine. It works. It has some bugs, but once it figures out that there is no cam sensor and the CEL comes on it runs great.

 

[Nalanthi]

All the 94 Explorers were up to Cali emissions. It's much more forgiving than an OBDII system would be though. I have a 94 Ex harness and 94 SEFI comupter in my truck on a 92 engine. It works. It has some bugs, but once it figures out that there is no cam sensor and the CEL comes on it runs great.

I owe you big time for the moral support here...

After last night's wrench & wire session, the truck is SO close to being done - only caveat being the driver's side.
ECU and pump are firing - haven't yet run the R/B wire from the starter to the starter solenoid yet. That is coming when I get these wires sorted out.

Am I trying too hard to rely on BroncoII's PDF with the 2.9 to 4.0 pin swapping/wire splices? The plugs on the 2.9 match up and I have them taped and labeled for easy ID... the 4.0 side - not so much.

My presumption is that I'm going to have to wire individual components separately one by one - the only thing I lack is a diagram or description as to what components the driver's side jumble is feeding. Looking at the plugs vs. the diagrams, I assume that no single plug serves a single function - i.e. ignition switch. Rather, the wires from one component are running to different plugs.

Damn shame there isn't a white plug diagram or master wiring diagram.

(added bonus - hell yeah I tagged your links. Keep up the good fight, my brother)

 

[adsm08]

Uh, here. I made this when I started do my wire work. I found out that a lot of it is wrong, but the important stuff is right.

It only applies to the Explorer.

http://therangerstation.com/forums/showthread.php?t=140738

Here is the Ranger connector on the dash side, just go off the circuit numbers for function. Circuit numbers stay the same across pretty much all of Ford.

 

[Nalanthi]

Uh, here. I made this when I started do my wire work. I found out that a lot of it is wrong, but the important stuff is right.

It only applies to the Explorer.

http://therangerstation.com/forums/showthread.php?t=140738

Here is the Ranger connector on the dash side, just go off the circuit numbers for function. Circuit numbers stay the same across pretty much all of Ford.

That... is gold. Pure and simple.
I owe you a pound o' flesh.

Another evening with another fresh set of eyes on it and I started splice/swap matching the colors that never changed between 90 and 94. I have a few wires to go...

Systems are for the most part operational - solenoids click, the nss is in and she turns over.

...just that handful of wires and potentially no spark.

I'm gonna use that diagram and dig around a bit - thanks again.

 

[Nalanthi]

That... was the missing piece. Can't thank you enough.
I still have a few wires that I'll need to figure out, but the most important functions are up and running.

The BII stirred and woke up last night - albeit cranky sounding with a new heart and a still disconnected exhaust.

Aside from another few random components like the rest of the vac and hooking up the rest of the AC from the Exploder, she'll be ready to drive by this weekend (or early next week).

There were a few changes between the 89 writeups and what I found on the 90 - things I'll have to make notes for.

 

[work_in_progress]

Any tips for the one guy who did the 89-92 Exp. Swap? Cant figure out the vacuum lines!