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Identifing after market wiring harness

Bart

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Is there a way to id an aftermarket wiring harness as to which company produced it? My '75 Ranger has such a harness. After an engine rebuild there's a purple wire marked TFI start that was connected to the battery. I don't think that's correct. I'd think it should be in the start circuit. If there's a way to id the harness a schematic would also be nice.
After thinking and looking at this for a moment I believe this harness is for the efi/computer only. The oem fuse block is still there. My main concern is the TFI start wire.
 
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surfer-b

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I don't think that would be hooked to the battery, it sounds like its the TFI ignition wire like on the mustangs with a TFI module. Unhook it from the battery, with the ignition switch in the run and start positions see if it has 12v to it. I did a quick glance of the painless PDF instrucions in the engines section and did not see a purple wire anywhere, however you may want to look again for yourself just to make sure.

https://www.painlessperformance.com/Manuals/10113.pdf
 
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Bart

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Thanks, appreciate the help. It is a '90 mustang under the Bronco's hood.
I also went to the Painless for a manual on the '90 mustang engine harness. I'll see what's in it. Thanks again.
 
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Bart

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Maybe someone can identify the harness by the only two connectors that look different from anything I've seen in the past. Hopefully I can post them here. The 5 pin has this info on the end of each wire
Gray 5 lug connector has red wire pin #37, black grd wire pin #60, dark green wire marked TPS pin # 47, PIP dark blue pin #56, & signal return CTS with no pin #
I went on the Centec site and downloaded the manual. Things don't look like what I have. PO said that it might have been Ford Performance.
I believe this is a 5.0 mustang harness, not a complete Bronco harness.
I'm guessing that there should be another mate to the connector but I don't remember seeing one when I took this apart about 6 months ago.
The fact that the wire #37 wire doesn't go anywhere makes me think this is the reason why I have no power to the computer other than the KAM #1. My concern is also that the TPS wire should be connected to something but the TPS on the engine is there and connected to oem wire. WTHeck!!!????
 

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DirtDonk

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Could be the Ron Francis, or if older, could be the RJM version.
Either way, you already said it's got the stock fuse panel still, and that has TFI on it and the other wires and connectors look like the typical stand-alone EFI wiring harness.

Very similar to what the old Ford Racing harness would be too possibly, but I believe that the Ford harnesses used the old "salt & pepper shaker" connectors behind the engine.
Maybe 904Bronco would remember for sure, as he's used at least two of the Ford version.

But no matter what brand, yours is the EFI/Engine harness, not the chassis harness.

Paul
 

DirtDonk

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And the fact that you show it coming out of, or near the glove box, can we assume the EFI computer is there somewhere?
If you look at the picture of our EFI harness (WH EFI Wiring Harness you can see the similarities and the proximity to the main EEC connector.

Paul
 
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Bart

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Thanks Paul. The PO did mention Ford Racing but not sure. I'll check out the WH link to see if I get any more info. It must be a stand alone harness and yes the area in question is behind the glove box. Another area that might shed some light is the four fuses and four relays mounted under the hood on the passenger side inner fender. There is power there just waiting for the relay to be energized to do it's thing. I've ohm'd out the grd, and #37 wire from those relays to that 5 pin and there is continuity between them. The damn thing is keeping me up at night as it's now quarter to 2 in the morning.
I'll reach out to 904 to see if this stuff rings any bells with him.
 
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Bart

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Paul, after looking at the WH link I believe we have a winner. The PO did mention that he "thought" he bought the harness from a company back east. That could be the Ron Francis company. I'll call you guys in the morning to see if I can pick up a few parts for this harness. Thanks again.
 

DirtDonk

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By now you may have called, but I'll say it here anyway, that we're not likely to have individual components for anything involving the EFI harness. It's built complete and that's it.
What type of component are you going to be needing? We might be able to get an individual connector, or might not. Never had to ask for one from them before.

That "company back east" could also have been RJM (the originator of the harness) as well. I believe Ryan was in Michigan, which is certainly back east from us way over here!

So what is it you're needing?

Paul
 

DirtDonk

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And regarding the TFI START wire, because it says "start" but mainly because it's Violet/Purple in color, it's almost a 100% guarantee that it needs to be connected to the start circuit of the vehicle. The most convenient spot is usually the "S" post of the starter relay, OR the "I" post if you are not connecting anything else there.

It's a start-retard function among other things possibly, but if you have battery power to it all the time your engine won't rev up because the ignition timing is retarded during START and won't like it when it's not needed.

Paul
 
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Bart

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And regarding the TFI START wire, because it says "start" but mainly because it's Violet/Purple in color, it's almost a 100% guarantee that it needs to be connected to the start circuit of the vehicle. The most convenient spot is usually the "S" post of the starter relay, OR the "I" post if you are not connecting anything else there.

It's a start-retard function among other things possibly, but if you have battery power to it all the time your engine won't rev up because the ignition timing is retarded during START and won't like it when it's not needed.

Paul
Paul, thanks for the info. I moved the TFI start to an ignition source, but with this info I guess I should move it again to a start post on the solenoid.
Thanks to your info, I found the three prong connector close to the master cylinder for the brakes with a wire marked run so I'll get it back inside and connect it to the ignition post on the ignition switch. Thanks for sharing your knowledge of this.
 
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Bart

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By now you may have called, but I'll say it here anyway, that we're not likely to have individual components for anything involving the EFI harness. It's built complete and that's it.
What type of component are you going to be needing? We might be able to get an individual connector, or might not. Never had to ask for one from them before.

That "company back east" could also have been RJM (the originator of the harness) as well. I believe Ryan was in Michigan, which is certainly back east from us way over here!

So what is it you're needing?

Paul
99.44% sure it's a Ron Francis harness. I spoke with them this morning and purchased a fire wall gourmet. We spoke of the three wire plug near the brake cylinder.
 

DirtDonk

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Excellent. Glad they had what you needed.
Have you had the whole thing up and running before this? Or are these the final steps before first startup?
You owned the Bronco and someone installed some of the stuff, or much (or all?) of this was done by a PO before you got it?

Can't wait to hear it's all dialed in and you're out enjoying it!

Paul
 
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Bart

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Morning Paul, almost 3 a.m. (again). The short of this is that I bought the rig from a guy a couple three years ago. It was a running mustang powered C4 Bronco. I haven't used it much as my '66 Bronco is the go and play in the rocks vehicle. I decided to rebuild the engine and change to an AOD trans. Clean, paint and generally make it a "Mall Crawler" High curb edition;D It's a Ranger so it "had" the nice interior. I was told by the guy's dad that this Arizona Bronco only had 30K miles on it and was perfect when son got a hold of it.
Anyway, rebuilt 5.0/AOD and no start. It cranks but that's it so far. I sent you a p.m. explaining all this but for the benefit of others I'll proceed. After finally getting the installation instruction (thanks to you) I went step by step to make sure nothing got forgotten. #22 wires with three prong plug for oil, temp senders AND power to the harness isn't providing the power to the relays or computer. NOTE here the three wire plug under the hood is NOT connected to any thing under the hood. I'm ASSUMING that the connection for the relays/computer takes place some where between the ignition switch and the end of the unused plug. I get 12 volts at the red wire under the hood (3 wire plug) that's marked "Feed". I'm convinced my problem is here. The area is not very accessible so I'll be removing the plenum for better access. Question, Is it possible that the power for the relays comes from connecting the power wire to the oil/temp sender wires??? I would not think so, but at this point I'm ??????????????????????? Broken wire right at the fire wall (maybe from engine installation) could be the problem also. GOD I envy people who sleep through the night%)
 
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Bart

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Excellent. Glad they had what you needed.
Have you had the whole thing up and running before this? Or are these the final steps before first startup?
You owned the Bronco and someone installed some of the stuff, or much (or all?) of this was done by a PO before you got it?

Can't wait to hear it's all dialed in and you're out enjoying it!

Paul

PO. I've been working on rebuilding engine/trans/Ford disc brake with new lines etc. etc. etc.
 
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Bart

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Up date to all. After removing the plenum, I was able to find the other half of a 3 way plug that feeds power to the relays and computer. Discussing and cussing with Dirt Donk's help I feel I have it figured out. In the morning I'll do some wire splicing (solder and heat shrink). Replace the plenum and I'm confident that the rig will start the newly rebuilt engine/trans.
Thanks to all who have offered input.
 
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