help hardwiring alternator , lost
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From: Spring / Sealy, TX
help hardwiring alternator , lost ok, ive trusted people to do wiring on my car enough, im just gonna have to figure it out
from my understanding
to make the alternator work you run the wire from the back with the 13mm nut on it straight to the positive terminal
and you use the 3rd plug from the motor, or 2nd from the outside to something in the wiring harness someone else did for me.
question
how do i wire it, to a switch so i can just turn it on/off when i start the car. its a racecar with a shitload of switches already, one more wont really bother me.
can i just run the excitor prong or whtever it is to a on/off switch then to the negative terminal on the battery, or something similar? how does this work, does anyone have a simple wiring diagram? ill just make a completely separate harness for the alternator. but im tired of it not working and beign told its working when its not.
im also a wiring noob, i know how to use butt connectors (ghetto) and guages of wire and thats about my extent of knowledge right now.
from my understanding
to make the alternator work you run the wire from the back with the 13mm nut on it straight to the positive terminal
and you use the 3rd plug from the motor, or 2nd from the outside to something in the wiring harness someone else did for me.
question
how do i wire it, to a switch so i can just turn it on/off when i start the car. its a racecar with a shitload of switches already, one more wont really bother me.
can i just run the excitor prong or whtever it is to a on/off switch then to the negative terminal on the battery, or something similar? how does this work, does anyone have a simple wiring diagram? ill just make a completely separate harness for the alternator. but im tired of it not working and beign told its working when its not.
im also a wiring noob, i know how to use butt connectors (ghetto) and guages of wire and thats about my extent of knowledge right now.
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From: Spring / Sealy, TX
this is what imn talking about, the B prong, what can i wire that directly to to charge my system constantly with a flip of a switch, or can i just hardwire it straight to the battery somehow?
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ok for future reference if anyone else does a search, i understand the back 13mm goes straight to the positive, and on the prongs on the plug you will see 4 letters on the side, P L I and S. Run one wire off the L terminal to an ignition switch, or a switch, that is hot when the car is on. you can hardwire it to the battery but you will drain the battery. but the activation switch is the L prong.
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From: Spring / Sealy, TX
and just to add, never let anyone do your wiring. ill be changing out my alternator for the fourth time today because something is amuck in my wiring, go figure
your problem is tha pin b needs to go to pcm slot 65 blue connector if its a 98 harness. the problem is that your running that thing 100% and maybe even at a higher voltage overcharging and killing it. luckily you didnt fry the harness. ask me how i know ?! 
. however you need a resistor for that wire between the plug and the pcm. on your rear heavy gauge wire that runs from the stud. just run it to the battery like you wanted to.
. however you need a resistor for that wire between the plug and the pcm. on your rear heavy gauge wire that runs from the stud. just run it to the battery like you wanted to. 
The alternator needs 12V on the exciter.
But like ex-SS-ive said, the reference voltage to the exciter goes through the guage cluster adding resistance.
Eventually, a full 12V signal will kill the voltage regulator inside the alternator.
I wired in a 1K ohm 10W ceramic resistor between the 12V reference and the alternator.
I would also suggest you run the referenced voltage through a relay and have the switch inside the car operate the relay. This minimizes the amount of current flowing under the dash (electical short and fire) and makes the switch last a lot longer (don't want to have a switch fail while exhibiting yo madd skilz)
I have my race car powered on 3 switches located where the HVAC/Radio control were ...
1 sends 12V to the PCM, fuel pump and the exciter field of the alternator
1 feeds power to the guage cluster and brake lights
1 feeds power to the radiator and oil cooler fans
And all 3 are on a master disconnect that kills power to everything and completely isolates the alternator and battery
I have a 4th switch which is a momentary switch that feeds the starter.
Since this picture was taken
http://www.vilipend.com/~frrax/album...4/CMC_9_05.jpg
I added the fans switch.
But like ex-SS-ive said, the reference voltage to the exciter goes through the guage cluster adding resistance.
Eventually, a full 12V signal will kill the voltage regulator inside the alternator.
I wired in a 1K ohm 10W ceramic resistor between the 12V reference and the alternator.
I would also suggest you run the referenced voltage through a relay and have the switch inside the car operate the relay. This minimizes the amount of current flowing under the dash (electical short and fire) and makes the switch last a lot longer (don't want to have a switch fail while exhibiting yo madd skilz)
I have my race car powered on 3 switches located where the HVAC/Radio control were ...
1 sends 12V to the PCM, fuel pump and the exciter field of the alternator
1 feeds power to the guage cluster and brake lights
1 feeds power to the radiator and oil cooler fans
And all 3 are on a master disconnect that kills power to everything and completely isolates the alternator and battery
I have a 4th switch which is a momentary switch that feeds the starter.
Since this picture was taken
http://www.vilipend.com/~frrax/album...4/CMC_9_05.jpg
I added the fans switch.
Last edited by mitchntx; Aug 29, 2006 at 07:32 AM.
