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99/01 alternator wiring question.

29K views 47 replies 9 participants last post by  Eatonualive281 
#1 · (Edited)
I ran a new wire from the trunk to the alternator, through the kill switch. On the Cobra there is a light green wire tapped into the stock alternator wire near the distrubution box. Any idea on the purpose of the wire? Is this the generator trigger wire? If this is the case you should connect this wire to the middle wire on the 99/01 alternator harness correct?
Also does anyone have a diagram of what wire connects to what when changing from a 03 to a 99 style? I found TRBO VNMs instructions referencing pass and driver's side but I don't have my alt here to see which way the connector goes on.

Thanks
 
#2 · (Edited)
Re: Batt relocation/kill switch with 99/01 alternator question.

Ok,I found a diagram of the lt grn wire. It looks like the lt grn wire is connected on one end to the yelow/white wire(alternator harness) via a fuse in the junction box. The other end is attached to the alternator output. What is the purpose of this and what should I do with it for a 99 style alt.? Wiring and me are like oil and water,lol.
 

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#10 ·
Re: Batt relocation/kill switch with 99/01 alternator question.

Ok,I found a diagram of the lt grn wire. It looks like the lt grn wire is connected on one end to the yelow/white wire(alternator harness) via a fuse in the junction box. The other end is attached to the alternator output. What is the purpose of this and what should I do with it for a 99 style alt.? Wiring and me are like oil and water,lol.
on my 99 wiring diagram and 99 cobra

the LG/RD wire gos from the regulator in the alt to the instrument cluster charge indicator lamp and then to the Central Junction Box. Circuit 904, Page 12-2 "C" connector 154 on alt.

The other wire, the VE/WH gos from the alts internal regulator to the Battery Junction Box. Circuit 36, connector c154 on alt to connector c100

The other other wire, the WH/BK terminates in the harness (it appears its not used) Circuit 4, Connector c154 on alt. to connector c100.
 
#3 ·
Rod,

if you can find what I posted, it should say what to do.

the middle wire I run to the power dist. box and fuse it. the 2 outer wires connect to the stock wires.

the green/red goes to the passenger side of the connector and the yellow/white goes to the driver side of the connector.
 
#4 · (Edited)
Jason,

I don't have my alt yet, it is at coating. Which way does the connector face? Flat side forward or aft? Also,the stock 03/04 Cobra alt cable has a green wire tapped into it near the fusible links, this wire comes from the connector under the dist box, the one that has the other 2 alt wires in it. I'm thinking maybe I can run it to the center terminal on the 99/01connector? I replaced my alt cable with one running to the trunk. It would be simple enough to run the lt green wire to the alt output and run the center terminal on the plug to the pwr dist box, but if I can elimitnate double wiring I would prefer to do that.

Any idea if that would work?

Edit- I don't think that will work.I just metered the lt grn wire and it has no continuity to the junction box lug. Anyone know what the lt grn wire is for? lol.

Thanks
 
#7 ·
not sure what the lt green wire is for. I don't have my manual with me. I just know I hooked it up per hellion instructions.

as far as how the plug faces, I assume you are talking about the pigtail harness you need for the 99/01 alt. from the instructions it looks like the flat side, meaning the side that doesn't have the clip on it goes towards the front of the car. that should also be the side that has rounded edges, correct?

I have a pic, but it is small from the instructions and I tried saving to host it, but the quality is very poor. let me know if that helps you out.
 
#16 · (Edited)
+1

Because the Hellion instructions say to wire it up to a fusible link on the pdc.
I wonder why? If it isn't used by Ford what would make Hellion instruct it to be hooked up? Maybe there is a reason. My .02 I wouldn't blindly wire up a FORD component in a way that isn't consitistent with Ford schematics based on another companies instructions without explanation/clarificatrion. I can't see the Hellion kit causing a need to wire the alternator differently than Ford would wire it in it's OEM use. The kit has nothing to do with wiring the alternator. Is I'm not real good/electrical with wiring,but a few people who are, agree after looking at the shcematic that the wire is not used. Why is it there then? Who knows. Maybe someone who knows for sure will chime in.

for the 03 or on the 99? maybe the 03 plug isnt shorted and actually powers something?
03 Cobra alternator harnesses only have 2 wires.

ON the 99 alternator wiring harness the third plug lead dosent go to anything.
 
#19 ·
on the non 4.6 (3.8 and ???)it its used. circuit 4, it goes from plug c154 to plug c153 its what is used to power the stator wires in the alternator. 154 is the three prong plug onthe alt c 153 is the single plug.

I wouldnt hook it up personally. Setting your self up for trouble.

Do what you want its your car.
 
#23 ·
hey guys,

the pic of the hays manual is of a pic for the 3.8.

It IS NOT FOR THE 99 COBRA!!!!

there are a few slight differences.


Again,

BK/OG (black/orange) (connector C1006-10mm nut/stud to fusible link A-12ga Grey)

YE/WH (Yellow/White) (connector C154 to C100m then the Battery Junction Box (Marked ALT-20A fuse)

LG/RD (Light Green/Red) (connector C154 to C100 then C107 then C331 then C250 at the Instrument Cluster as the Charge Indicator Lamp and then back thru C250 at the cluster to splice 257 and then to the Central Junction Box #5 - 15A fuse)

Thats it. Nothing else is used on a 99 style Cobra alternator.

There is a WH/BK (White/Black) comming off the Alternator (connector C154) that terminates in the harness (it is connected to NOTHING)

I would not connect the WH/BK wire unless you really want to possibly start an electrical fire as it appears it might be an un-used stator power wire that should not be used because the stator is already powered by the regulator internally. You will probably mess up the regulator and cost yourself a new alt.


This stuff shouldnt be that complicated. I like Hellion but I know my 99 wiring pretty well.
 
#26 ·
Again,

BK/OG (black/orange) (connector C1006-10mm nut/stud to fusible link A-12ga Grey)

YE/WH (Yellow/White) (connector C154 to C100m then the Battery Junction Box (Marked ALT-20A fuse)

LG/RD (Light Green/Red) (connector C154 to C100 then C107 then C331 then C250 at the Instrument Cluster as the Charge Indicator Lamp and then back thru C250 at the cluster to splice 257 and then to the Central Junction Box #5 - 15A fuse)

Thats it. Nothing else is used on a 99 style Cobra alternator.

There is a WH/BK (White/Black) comming off the Alternator (connector C154) that terminates in the harness (it is connected to NOTHING)

I would not connect the WH/BK wire unless you really want to possibly start an electrical fire as it appears it might be an un-used stator power wire that should not be used because the stator is already powered by the regulator internally. You will probably mess up the regulator and cost yourself a new alt.

This stuff shouldnt be that complicated. I like Hellion but I know my 99 wiring pretty well.
The schematic could be for multiple models, that is also how the alldata schematic works. In any case,even the above schematic agrees with what you are saying IMO. The Blk/Wht wire really goes nowhere. At this point if someone isn't convinced then they probably won't be.

:beer:
 
#27 ·
I will talk to some others, but on my orange cobra it was hooked up for about 15k miles with no issues and I know a lot of others are with no issues reported. but I will see if I can look into it more.

my current car it is hooked up the same way for 2500 miles now and no issues.
 
#28 ·
Ive been re reading the thread,

We are talking about putting a 99 style alternator on an 03 style harness right?

There could be a different wiring diagram for the 03 that needs power to that unused wire... It may not go to the stator windings and may be a voltage ref for an o3.

Does Hellion use a generic alternator plug or do they use a 99 style? I need to look up the 03 wiring harness and see the difference... Ill have to do that as soon as I have access to the pTS website.

ubil
 
#36 ·
Rod, I see you have your car fired up now. What wiring did you end up going with?
 
#37 · (Edited)
I did not hook up the center wire. And it charges great. About 13.8-14v at idle, never drops below 13.7ish at high rpm when logging battery voltage..and that is with the alternator lead running to the back. I am pleased so far. I was concerned that I might not have ran a large enough alternator wire(4ga StreetWires) but the voltage drop seems to be minimal.

ps How is your beast doing? Destroy any trannys lately? lol
 
#38 ·
A few guesses for ya,

I know the EEC looks at battery voltage to correct the fuel maps since the higher the voltage the more power the fuel pump shoots out so the EEC figures that in,

The 2nd wire would probably be the stator wire
The 3rd would probably be the gauge clusters low battery light.

It was alot simplier to do a 3g conversion on a fox stang. I don't have a wiring manual for these cars yet so these are guesses.


Your 4 gauge wire is more than enough for the altenator. The stock 130amp alternator had dual 8 guage feeds on the sn95 and the fox body conversions.
I will try to find a wiring diagram and look

B
 
#39 ·
A few guesses for ya,

I know the EEC looks at battery voltage to correct the fuel maps since the higher the voltage the more power the fuel pump shoots out so the EEC figures that in,

The 2nd wire would probably be the stator wire
The 3rd would probably be the gauge clusters low battery light.

It was alot simplier to do a 3g conversion on a fox stang. I don't have a wiring manual for these cars yet so these are guesses.

Your 4 gauge wire is more than enough for the altenator. The stock 130amp alternator had dual 8 guage feeds on the sn95 and the fox body conversions.
I will try to find a wiring diagram and look

B
check post 23:whistle:
 
#46 ·
I really hate to bring this back from the dead, but i cant seem to find the info i need. I've looked all over... long story short, I have an 03 cobra, turbo car with a 99-01 alternator. i have an all black generic pug and pigtail for the alt. I know where these wires go...they go to the plug in the harness that has 4 wires. green/red, yellow/white, white/red, and a solid green wire. My question is, where do the solid green wire and the white red wire go? what do they get wired to? Thanks guys.
 
#47 ·
Just terminate them in the harness. They are unused, as is the center wire in the plug when using a 99/01 Alternator.

Yellow / White to the left terminal. Light Green / Red to the right terminal. This is looking at the face of the connector with the lock tab at the top.
 

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