LogicFoxX

iTrader: (2)

Hey gents, in my process of switching alternators using bits of information from each thread on the subject, I've ran into some problems.

First, let me start off, I assumed the bosch alternator i received from auto parts warehouse was good due to the inspection plate. However, after wiring in the new FD alt and running the car, the alternator did not charge what-so-ever at any rpm (remained 11.1 V the entire time). After sleeping, I checked the battery voltage at dawn and it was down to 10.9. This made me believe that I either misread some information and wired the alternator wrong or the alternator was faulty to begin with.

The first step I decided to do was check the alternator for the 1-3 V at one of the terminals when ignition sw is on, I think L? And one terminal was 12V and the other was 3ish (might of been slightly higher or lower). Then decided to get the alternator checked at napa, to my disappointment/surprise the alternator checked bad at DC Charging. I also can't help but wonder if I burnt something up.

Question is, did I go wrong somewhere or could just be bad alt?

And heres my wiring (pics):
Using original harness for L Terminal, (Cheap Vamp Splice on connector and heat-shrink/solder at harness)20 gauge wire connection (cyan/blue)

Using 18 Gauge wire at S terminal (heat-shrink/solder connection) to what I believed to be the + side of the EGI fuse (Red)

Original B Terminal, reamed out to fit the larger bolt and filed down to connect to the metal and allow the new nut to sit.






And on a side note, I took ohm'ed out gnd to + and - of the battery terminals (of course with no battery) both read continuity. I did this to my friends 86 FC as well, same reading, why is this?

Anyways, thanks for taking the time reading, lol.

misterstyx69

iTrader: (142)

Damn..I got a diagram on this but I have it on Desktop,and I am Illiterate as hell when it comes to this computer ****..Search FD alternator swap..and S5 alternator..there should be a Diagram on All 3 types(s4.s5.and FD) on one of the threads there.good luck man.

HAILERS

The plug Seems to be done right. See attached jpg stolen off the net. I look at your jpg and look at the elect plug and see that if in that picture, if you flip the plug over with the key at the top, then the power wire will be on the left (looking in the wire side of that plug), which would be right.

The other wire has nothing to do with the alternator charging. It would go to the White/Black on the original series four harness.

helghast7

iTrader: (6)

http://www.cardomain.com/member_page...9_222_full.jpg

hope that helps any

LogicFoxX

iTrader: (2)

Well maybe it is just the alternator, am I correct to assume that the S terminal needs a constant 12V even when the ignition switch is off to prevent battery discharging?
Secondly, whats with both positive and negative battery terminals grounded? Third, is it possible to burn my alt out with those connections?

Anyway thanks, yea I did use that drawing and the other one that shows the new wire to egi fuse. Here is a simplified schem of my wiring, sorry my mouse sucks.

HAILERS

As you can figure out, I'm easily confused. Attached is a jpg. Looking into the rear of the alternator the pin on the left is the one recieving batt voltage from a constant source of batt voltage, like the EGI fuse. The S terminal.

helghast7's picture Seems confusing in this respect: The back of the alternator looks right but if you look at the elect plug off to the left, it SEEMS to be viewing the plug from the side away from the where the wires enter, so that would be wrong. Right? Yes, wrong.

But the back of the alternator seems right. Plus they have the S voltage coming from the original plugs black/white wire which is NOT a constant source of batt votage. That is a Switched source. You do not want a switched source for the S5 S terminal. Right? Right.

And in the last jpg of LogicFoxx, yes, you need to dead end the original Black/White wire.

Also see the ammended jpg I attached and the words on the bottom. It tries to explain what I said above about that picture. I tried to color the words but for some unknown reason it won't take color??????

That sucker should have worked if you had the pwr from the EGI fuse going to the S terminal (one on the left as you look into the alternators jack). Swap 'em around and it'll kill the alternators regulator...eventually.

LogicFoxX

iTrader: (2)

Alrighty, I'll leave it the way it is, maybe ditch the vamp splice and use solder instead. Appreciate it Hailers.

Going to rewire in my s4 alt and do some voltage reg checks, and make sure S terminal is a good 12v source. Thanks Guys for the support.

nyc_scorpio

iTrader: (1)

Just do what you can see in the pictures, I installed FD alt in my S4 and I always have 14.4 with 2000W stereo on, A/C, HID lights. cant go wrong...

On the first pic, the top plug that runs direct from the alt, goes direct to the battery.

Also direct to the battery, I ran the top plug, the one your see with a rubber gasket, to prevent it from hitting the top mount intercooler.

the the last plug, the bottom one, goes to the wire that came off the S4 harness, the L terminal. the other left over cable, just make sure you put alot of electical wire around it and if you can insulate it, better.

I recommend that you use some good gauge wire, since we are talking about your life line on the car also, go to the home depot and get high temp insulation rubber and some zip ties and just do what I did and keep it all clean and insulated...

nyc_scorpio

iTrader: (1)

that last picture of that positive, you will not use it on the FD alt, cap it off, electical tape it, insulate it really good. This wont work with the FD alt....

helghast7

iTrader: (6)

ok that just kinda made it really confusing....there should really be an easier way to explain this ****

LogicFoxX

iTrader: (2)

Wow man, you went alll out, is that 4 gauge?
My Battery is relocated to the cargo bin, so preferably would like to tap off another power source but if not, running wires is my specialty.

You said don't use the original B terminal, thats okay with me, but why is that?
Thanks for the input.

HAILERS

***about the question in the last picture above.*****

The pos and neg ohm'd out to each other because every light bulb in the car goes from positive to ........gnd. Most componets in the ECU go to gnd, and on and on and on and on.

It is odd that you new alternator did not work. You say you had the approx 3vdc on the L terminal (the one on the right as you look into the small alternator plug). That meant the regulator in the alternator was supplying exitation voltage. Shoulda worked. I've no idea why it didn't. See page G-9 of ENGINE ELECTRICAL in the series five FSM. But you seem to have already done that.

nyc_scorpio

iTrader: (1)

yes sir, 4 gauge, cant go cheapo on good wire for electrical. about no using the B terminal. The FD alt will is basically on constant on, since it is direct to the battery, you will just drain your battery.
The S4 B terminal is on a relay of some kind. You dont need this with the FD alt, just bypass it. I have been running my FD alt like this for about 3 years with no problems what so ever.

Helgast7--- I know it seems crazy, but it works. I cant really explain it, but I was showed to conect it this way by a electromechanic and man-o-man I was last night cranking 96db of music and the lights on. on a dead stop I saw NO DIMMINIG of my lights. then again, I never have dimming of the lights since going FD alt.

RoughRex

Ok... I'm not an electrician so sorry if this is a dumb question.

If on the FD and S5 Alts both B and S connect directly to Battery (+) Why would you not just run a jumper from B to S?

LogicFoxX

iTrader: (2)

Correct me if I'm wrong, but looking at the FD FSM alternator layout, it seems that the S terminal determines the draw that the battery takes and B charges the battery. Or something to that extent. But then again, the wd doesn't show the whole lay out so i could be wrong =).

*edit* and actually looking at this again, I really couldn't tell ya how it works but it does seem S has it's own function.

nyc_scorpio

iTrader: (1)

I dont know how that works out, I understand what your saying about jumping the wire, since they are going to the battery post, I just like to have seperate wires dedicated to themselves..
But I **** you not. I was thinking, well 2 outta 3 connections are to the main battery and the last one will do its thing. I was skeptic, but I saw it work, and still works.

helghast7

iTrader: (6)

ok let me understand this correctly.....the B terminal goes straight to the battery? why cant you just run it to the stock s4 connector?
same with the L terminal, were does it go exactly on the s4 harness or what not?

and the S terminal is blocked off correct?

nyc_scorpio

iTrader: (1)

yes, on the S4, the B and R terminals are blocked off, on the FD alt, you will make these go direct to the main battery post.

HAILERS

The Large wire called B, is SUPPOSED to run to the MAIN FUSE. It, the Main fuse, in turn feeds the battery THRU the Main Fuse. It's also spliced to a wire prior to the Main Fuse, and that spliced wire feeds the ignition switch.

The wire from the S terminal is fed FROM the EGI fuse.

Fuses are there to protect electrical circuits. See free online FSM's.

Akagis_white_comet

iTrader: (4)

Okay, from what I've gathered in this thread, here's how things are wired up a FD alternator in a S4 FC:

FD Alt S4 Car
B Terminal--- Battery Positive terminal
L Terminal----L Terminal
S Terminal----Battery Positive terminal

As for the S4 Car's B and R terminals, these are to be bypassed and insulated, correct?

Last, what gauge wire would be a good idea to handle the current? In my car, I used 12-gauge and am getting nothing. I saw that NVC Scorpio used 4-gauge for the whole install. Would 10-gauge be sufficient to do the job?

GuiltySoul

iTrader: (7)

ok guys i know this is a old bump but i need help and and need more info before i start cutting wires. yes i searched thats how i got this.

so from the FD alt:
the B terminal goes directly to the battery via a fuse or not?
L goes to L
S terminal gets spliceed to EGI fuse

On S4 chassis:
oem B terminal gets capped off/ unused
oem R terminal gets capped off/ unused

now for the B terminal from the FD alt do u need to splice it to the MAIN FUSE or can i just add my own fuse going to the battery?

let me know if this sounds right or if im way off. asap guys i wants this done!!! lol

dwb87

iTrader: (22)

The B+ wire comes from the fuse block (Specifically main fuse). Does this wire not exist in your engine bay?

GuiltySoul

iTrader: (7)

I said that to, so I just put the oem B terminal on the FD alt then? Other people on here ere saying deferent

dwb87

iTrader: (22)

I would assume you would attach the wire straight to the B+ terminal. I don't have an FD alternator, but I do have a Taurus alternator... And the large "B wire" attaches straight to the B+ terminal on the alternator. This thread is somewhat confusing. I only read through it a little bit, though.

bumpstart

s4 chassis will be lacking sufficient B+ cable diameter to utelise the s5 or s6 alt correctly,, B+ must be upgraded

easiest way to do this is splice another B+ cable ( 8 AWG ) [ same diameter as the original ] to the other side of main fuse ( EGI )
( the side with only one bolt )