I think my 60Amp alt is failing, question about 3G

[adam.w.ackerman]

Install is done and I have no power anywhere. I thinks it is because the yellow wire is no longer connected to the solenoid. The diagram I was looking at shows it connected to the charge post but I think it still needs to run through the loom across the front and remain connected to the solenoid with the old charge cables. Of course I hacked the solenoid end off to repurpose between the solenoid and mega fuse. Can anyone confirm this? I tried back feeding from the charge post but nothing changed.


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[VicCrownVic]

The yellow wire goes right to the alt charge stud on mine and works fine. The only wire that goes to the stock location is the green wire.

Is the mega fuse good?

[adam.w.ackerman]

I think my 60Amp alt is failing, question about 3G

Yes, I get battery voltage all the way back to the alt, but none of the cars circuits have any power. Car side of the CB on the solenoid even has power. That's the only main break in the circuit right? From there it goes to the fuse box and is distributed, right?

Mine is a 89 and I saw a similar post on a truck forum that said the yellow had to remain stock. I also see now that the section I cut out and repurposed is a fused link.

I had to have screwed something up.


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[Kodachrome Wolf]

When I did my 3G install, I didn't bother the factory voltage regulator plug. Only modification I made was cutting the white stator wire from the 2G plug. That allowed me to put the singular pin stator plug on the 3G.

Does the 'AMP' light come on/stay on the dash?

[adam.w.ackerman]

Nothing comes on, the car has no power. I have battery voltage to the alt and the car side of the CB on the solenoid.

No lights
No dinger
No crank

Notta


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[VicCrownVic]

That means the new charge cable, including the mega fuse, is good (I know you already knew that).

Now, when you say no power you mean you turn the key on and you have no lights, no door chime (if you still have that), etc.? Everything other than that yellow wire was hooked back up to the fender mounted solenoid and on the same post it came off of?
My '89 EVTM is at home and I am not so I might not be entirely accurate, but I'm pretty sure removing the yellow wire from the solenoid should not cause anything to lose power. The stock yellow wire was attached at the solenoid and not spliced into the 2 stock charge cables? For some reason I thought I saw it spliced into the charge cables, but I'm not too sure.

[gadget73]

Part of what the wire over at the solenoid does is split to feed various other things. You need to re-connect that so you have power to the car. Some didn't do this, later ones do. If you follow that you should find that the single yellow splits to several fuse links, the alternator feed among them.

[adam.w.ackerman]

Part of what the wire over at the solenoid does is split to feed various other things. You need to re-connect that so you have power to the car. Some didn't do this, later ones do. If you follow that you should find that the single yellow splits to several fuse links, the alternator feed among them.

This what I am thinking, I guess I am skipping work tomorrow and pulling the harness out of the header to fix my screw up. I should be able to weed it back to the yellow spice and just run a single feed right?


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[adam.w.ackerman]

That means the new charge cable, including the mega fuse, is good (I know you already knew that).

Now, when you say no power you mean you turn the key on and you have no lights, no door chime (if you still have that), etc.? Everything other than that yellow wire was hooked back up to the fender mounted solenoid and on the same post it came off of?
My '89 EVTM is at home and I am not so I might not be entirely accurate, but I'm pretty sure removing the yellow wire from the solenoid should not cause anything to lose power. The stock yellow wire was attached at the solenoid and not spliced into the 2 stock charge cables? For some reason I thought I saw it spliced into the charge cables, but I'm not too sure.

Key, no key ; nothing. No dome, no side lights, completely dead inside like me at the job I am skipping tomorrow.


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[VicCrownVic]

Gadget provided the detail I would have looked to the EVTM for. With that information: ignore most of what I said and reconnect the yellow wire back to the solenoid even if it doesn't go to the alt anymore.

[adam.w.ackerman]

Just trying to figure out if I screwed my self by cutting the fuse link. Those new to me, never messed with them before.


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[Kodachrome Wolf]

Just trying to figure out if I screwed my self by cutting the fuse link. Those new to me, never messed with them before.


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I cut out some of my old 2G harness by culling it right at the fusible link and then wrapping it in electrical tape and returning it to the wiring loom.

Did you take anything off of the starter solenoid? I've heard there can be issues on some cars if you take the old charging harness off from that solenoid since apparently they fed some other things. I know that stud does get kinda loaded with wires.

Here's my setup, while not the greatest photo, you can see everything, even though it's not the best:


The voltage regulator plug is a carry-over from the 2G stuff. Only modification was to the stator wire so it would plug into the 3G. The charge cable runs over the fan shroud, along the core support, and over to the starter solenoid and is bolted to the side towards the front of the car. Right at the solenoid is where the charge cable also hooks into its mega fuse.

[His Royal Ghostliness]

Looking at the '89 EVTM for you right now:

- power leaves your alternator via two black wires with orange tracers.
- at some point down the harness said two black/orange wires are spliced together into a single 14-awg fuse link (green in color, you have posted a good picture of it).
- from the green fuse link the wires split into two black/oranges again, pass thru that black 3-wire (two black/orange one yellow/white) connector (C875 in the EVTM), and disappear into the main harness.
- at some point the two black/orange wires splice into a single wire again, also black/orange and likely of a fatter gauge. From the same splice originate two fuse links which bleed power off to the ignition switch and some parts of the fuse panel. This splice lives in the main harness in the area near the relays behind the washer/coolant reservoirs, there is a grey 10-wire connector in its vicinity.
- that single fat black/orange wire then continues almost to the starter relay on the fender, where it splits into two fuse links - the 12-awg gray one hooks up to the starter relay on the post where all the other shit draws power from, and the 16-awg black one looks back to the alternator by ways of yellow/white wire which serves as your battery voltage sensing wire.

In other words, it's one giant clusterfuck. The cleanest way of going about is to disconnect connector C875 (the 3-wire one on the left fender's plastic inner liner (Ford calls it an apron btw), and remove the piece of harness that runs from it to the alternator. Do not disconnect any wires on the starter relay at all - I suspect you have identified the fat black/orange wire as your old charging wire and you have removed it from the stud, thus killing power feed to your ignition switch and fuse panel by ways of those two fuse links that branch off near the relays on the driver side fender. For battery voltage sensing wire just loop the thin yellow wire that comes out of your 3G 3-wire connector over to the charging stud of the alternator - your 1/0 charging cable is fat enough that there will be next to zero voltage drop between there and the battery itself, so all should work fine.

Edit: the single yellow/white wire in the C875 connector is for battery voltage sensing ONLY - it powers absolutely nothing else in the car, as doing so will defeat its only purpose for existence. Therefore you can do whatever the fuck you want with it, provided the other yellow wire (the one from the 3G connector) has a way of seeing battery voltage. You can splice the two yellow wires together if you wish, the only thing that accomplishes is providing you with a fuse link between the alternator charge output stud and the the voltage regulator. The downside is than now you have another wire that runs from the body of the car to the alternator - if you have a suitable factory-style connector that can accept flat-blade pins you can make this all factory-looking.

[adam.w.ackerman]

Excellent, thanks for that info! So do I need to source a new set of fuse links to replace the one I butchered or can I replace that removed section with a single heavy gauge wire? I think I have some 6 or 8.


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[VicCrownVic]

Replace it with an inline fuse. I'm not sure if the fuse link has any useful information printed on it (I think it might) to determine what replacement fuse would work.