[onecoomofo]

I have a 69 nova that has a serpentine setup from a 99 Tahoe. I'm running the A/C compressor, Alternator, and power steering pump on the setup.

However I have a problem with the wiring on the alternator. It has the main power wire going to it, as well as a plug on the side with 3 small wires going to it. 2 of the wires are looped, and the other one goes to a little light i put on the dashboard.

My friend said that it needs to have some type of 'load' on it, thats why the light is there. If you turn the ignition on, the light comes on, and when you start it the light turns off. I started it w/o the belt one day and the light stayed on.

Anyways, the alternator went out. This is the second one to go out. I'm not sure if it's the ghetto wiring or if i just have bad luck.

Plus, i know nothing about alternators. If anyone knows anything, can you please help?

Thanks
- Sean

[horvath]

There's some helpful stuff to read HERE

Alan
54 Chevy Pickup

[onecoomofo]

Does anyone know an easy way to make a 3 wire alt. into a 1 wire?

On the plug, there are 3 wires coming out, a red, a black, and a brown. The brown is hooked up to a 'warning light'. Where should the red and black wires go??

- Sean

[onecoomofo]

UPDATE:

I'm using the 10SI/12SI GM/ULTIMA replacement alternator for a 98 chevy tahoe for my car.

I've included a picture of my setup.

Again, the 'warning light' on the dash doesn't come on with the ignition anymore, and i tested the light and it works fine. Still won't charge the battery. Battery is fine.

What do you think is wrong?

Thanks again
- Sean

[onecoomofo]

UPDATE 2:

I went out and played with the car again. Found out something weird. If I connect an ignition hot wire to the blue wire that used to have the warning light, the alternator kicks on and starts charging imediatly. However, after the car is started, the light doesn't go off anymore (since its a hot coming from the ignition)

Well, at least the alt. is charging... but what did I do different to make the 'warning light' stay on?

Thanks
Sean

[camaroman7d]

All alternators work basically the same. The light on means the alternator is getting voltage but not outputting any (this is why the light comes on when you turn on the key and then goes out once the car starts). If the light is on and the alternator is charging something is not hooked up correctly (maybe the light). The alternator needs voltage to work, the difference between 1 wire and three wire (or more) is that on a one wire the alternator/regulator senses, receives and outputs all through the same post/wire.

What you need for it to work is a hot wire when the ignition is on, a sense wire (tells the alternator when to charge) and of course a battery charge wire. The indicator light is not needed, but can be handy.

If you need specific wiring let me know and I will post which wire/terminal should go where. I just went through this on my car. I installed a Acura alternator in my Camaro (the Acura had a total of 5 wires, they all work the same is what I found out doing my research)

Royce

[onecoomofo]

So basically if you look at the picture i attached....

I should take the red and black wire and change them? So take the red wire and put an ignition hot to it, and re-connect the black wire to the ground?

I hope i have the right idea here. Anything you can add?

Thanks
Sean

[camaroman7d]

I don't know what kind of alternator you are working with (looks like a CS130). You do not want to ground a hot wire to the case of the altenator (instant melt down). We nee to establish which terminal or wire does what. We know the big post/cable is the battery charge wire, that is the only known fact.


The terminals on the alternator should be marked.

P- is not used

L- use if you do not have a warning light and connect to the ignition (switched 12V source)

F- Used with light/indicator (connect a switched 12V surce here if you are using the charge light)

S- If present connect to the battery charge post on the alternator.

If you do not have the above posts/markings let me know what you have and we will figure out what altenator you have and go from there.

Royce


Edit:
I just re-read your post and it is a 10si, this is simple. Connect terminal 1 or R to a switched 12V source (this is also your warning light terminal) Connect terminal 2 or F directly to the battery charge post, this is your sense wire. The alternator is grounded through the case.

If you connect it the way I just described it should work properly.

[Mista_T]

I had similar problems and I'd like to second what Royce said. The big post goes to the battery positive. Then jump a wire from the big post to the closer terminal (2 or F). The the second terminal should go to a 12V switched source (on when car is running, otherwise off). Also remember that when the alternator is charging the charge is from from positive to negative so for optimum charging performance, run a ground wire directly from the alternator case (or ground terminal) directly to the battery negative. Good luck.