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jojoman 07-22-2011 10:09 PM

alternator plug
 
i just had a quick question i bought a plug for the alternator and it has 3 wires but i really only know where one goes so can any one help me on that is one thick onw and 2 thin ones

cr34t3d_by_d4rkd3n 07-22-2011 10:49 PM

Re: alternator plug
 
....???? what? ur truck should have a 2 wire set up, 1st wire reads the 12v from battery, and the other wire gives a 12v signal to the alt to start charging when the 1st wire says "under 12v, need to charge battery"..

its called a exciter wire, even tho theres 2 wires total.

if u have a 3 wire its wrong, and wont work. a common update for the 67-72 c-10's is to switch a 1 wire to a 2 wire.... but thats a whole-nother cup-a-tea

jojoman 07-22-2011 10:52 PM

Re: alternator plug
 
well the block is not thr original one for the motor and it ahs a serpentine set up so i got one for a 95 chevy and when i oredr the plug came with 3

cr34t3d_by_d4rkd3n 07-22-2011 11:02 PM

Re: alternator plug
 
u will need t find out what wire does what on the 3 wire, and swap it, im guessing 1 is a 12v sense wire, 1 is a 12v, and one is a ground, u need to know what is what on the 3 wire. sorry.

jojoman 07-22-2011 11:16 PM

Re: alternator plug
 
yea im pretty sure the thick one is the power the one that goes to wire harness the other one is probably is a ground or does one of the go in the bolt in back of alternator

hatzie 07-23-2011 12:24 PM

Re: alternator plug
 
Stock '95 trucks would have a CS130 or CS144 alternator. 73-87 CK use a Delco 10SI or 12SI.
Delco CS alternator plug pinout:
S = "Sense" heavy gauge wire to 12v ignition switched source.
L = "Lamp" Connect to the low side of the idiot light to energize or excite the alternator.
F/I = "Field" or "Ignition" Terminal (DO NOT HOOK UP TO THIS TERMINAL) On the later cars/trucks it has differing uses depending on the regulator installed. Some regulators have a resistor that is internally connected between the Field and Lamp terminal. Other regulators use the F/I terminal to feed field duty cycle to the PCM.
P = "Pulse or Phase" Terminal (Diesel Tachometer Signal)

Delco makes conversion wiring for upgrading from the SI to CS alternator. The harness Hooks Pins L and S to the 12SI harness plug. F & P are unused. The 95 probably used S, F/I, & L the GM T400 diesels are the only ones that might use all 4.

Delco P/N 8077, Haywire P/N 2110, Painless Wiring P/N 30707, Pico P/N 5327A (you must have an “Idiot light” to use these convertors. They don't include a resistor)

Delco P/N 8078, General Motors P/N12102921, Pico P/N 5327 SI-CS conversion adapters include a resistor for the “L-Circuit”. The resistor duplicates the electrical characteristics of a Lamp Circuit.

jojoman 07-23-2011 01:24 PM

Re: alternator plug
 
2 Attachment(s)
well these are the wire i got from the plug is 3 wires bottom one being the thickest oneAttachment 777542
and this is the only wire coming from truck so i know there has to be a ground but dont know which one and does the thich one go in the back of the alternator where it has the screw or does it go to this green one help pleeeeeaaasee Attachment 777541

hatzie 07-23-2011 03:39 PM

Re: alternator plug
 
4 Attachment(s)
The GREEN wires you have in the picture are likely the TEMP sensor wiring.
The Delco SI in our trucks uses a 2 position Packard 56 plug. Red is the Sense wire and Brown (white on this repair pigtail) is the Exciter wire.
Attachment 777586

Option 1 use the truck wiring from the Delco SI if it's not butchered. NOTE: I and F are the same terminal.
Attachment 777562

Option 2 Setup the Delco CS as a single wire alternator
GM Performance Parts tech sheet. NOTE: I and F are the same terminal.
Attachment 777585

Your repair plug annotated.
Attachment 777569

jojoman 07-23-2011 07:05 PM

Re: alternator plug
 
well the thing is taht it has a serpentine set up so the alternator is a delco cs so that why they gave me this plug and im tring to figure how am i suppose to set it up

jojoman 07-24-2011 02:09 PM

Re: alternator plug
 
got it done thank you guys it was so simple just i couldnt find the old wire once i did hook up "L" to it and "S' to bolt in bacof alternator and bang bang 13 volts quick so thank you guys oh the other green wire is for ac compressor


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