no alternator plug on Painless harness
Thread Starter
Joined: Nov 2001
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From: Houston, TX
no alternator plug on Painless harness Just wiring up the engine and discovered that there isn't an LS1 alternator plug on the painless wiring harness. I can probably get that plug (one wire out) from the dealership, but does anyone know how I should wire it up? Where does that single wire coming out connect to?
TECH Addict
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From: St Louis, MO
Connects to the dummy light in the dash. I checked the factory wiring diagram for my '66 and found the appropriate pin on the regulator harness to splice it into.
My LT1 painless harness did not have this either.
My LT1 painless harness did not have this either.
Joined: Nov 2001
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From: Anderson, Indiana
The easiest way to hook this up with a 98 PCM is to go from the alternator to a 500 ohm resistor,and then from the resistor to a switched ignition source (key on 12 volts). You can use a dash lamp instead of the resistor if you want, but it needs to be a bulb and not an LED.
On the 99 and up PCM's, the PCM controls the LAMP line directly.
On the 99 and up PCM's, the PCM controls the LAMP line directly.
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91 Z28 LS2 408CI, LS9 Supercharger, LPE GT7 cam, Yank3000, 3450 raceweight.
Latest numbers: 9.71 ET, 141.42 MPH, 1.40 60' , 610 RWHP Mustang Dyno
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91 Z28 LS2 408CI, LS9 Supercharger, LPE GT7 cam, Yank3000, 3450 raceweight.
Latest numbers: 9.71 ET, 141.42 MPH, 1.40 60' , 610 RWHP Mustang Dyno
www.speartech.com
Staging Lane
Joined: Mar 2004
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Alternator wiring
Originally Posted by Speartech
The easiest way to hook this up with a 98 PCM is to go from the alternator to a 500 ohm resistor,and then from the resistor to a switched ignition source (key on 12 volts). You can use a dash lamp instead of the resistor if you want, but it needs to be a bulb and not an LED.
On the 99 and up PCM's, the PCM controls the LAMP line directly.
On the 99 and up PCM's, the PCM controls the LAMP line directly.
The engine/pcm/loom are for year 2000 Camaro
Last edited by Uk Robert; Jun 23, 2004 at 08:04 AM. Reason: adding pcm year
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From: Tampa, FL
Originally Posted by Uk Robert
Hi, I`m over in the UK and have nearly completed an LS1 install into Ford (Mercury) Capri. I have a similar wiring question. The original wiring of the Capri consists of 3 wires. 1 from the fusebox, 1 from the battery and 1 from the dashboard warning light. Am I correct in saying that the fusebox and battery wires can be bolted to the large terminal on the back of the Alternator? My reconfigured LS1 harness from Fuel Injection Specialities has the one wire hook up into the 4pin connector on the alternator which just leaves my capri dashboard warning light wire. Where does this go to? Does this have to be connected somewhere in order to "excite" the Alternator? Any help much appreciated as this is one of the last things holding me up!
The engine/pcm/loom are for year 2000 Camaro
The engine/pcm/loom are for year 2000 Camaro
The other 2 wires (battery and fuse box) should indeed go to the stud on the alternator.
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From: Anderson, Indiana
The "GEN" or "ALT" light.
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91 Z28 LS2 408CI, LS9 Supercharger, LPE GT7 cam, Yank3000, 3450 raceweight.
Latest numbers: 9.71 ET, 141.42 MPH, 1.40 60' , 610 RWHP Mustang Dyno
www.speartech.com
91 Z28 LS2 408CI, LS9 Supercharger, LPE GT7 cam, Yank3000, 3450 raceweight.
Latest numbers: 9.71 ET, 141.42 MPH, 1.40 60' , 610 RWHP Mustang Dyno
www.speartech.com
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Verdad Gallardo Joined: Nov 2001
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From: Anderson, Indiana
The thing to note is that either a light bulb or a resistor is an important part of the circuit. Do not take a 12 volt line directly to the "L" terminal of the regulator (terminal "B" on the late style connector).
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91 Z28 LS2 408CI, LS9 Supercharger, LPE GT7 cam, Yank3000, 3450 raceweight.
Latest numbers: 9.71 ET, 141.42 MPH, 1.40 60' , 610 RWHP Mustang Dyno
www.speartech.com
91 Z28 LS2 408CI, LS9 Supercharger, LPE GT7 cam, Yank3000, 3450 raceweight.
Latest numbers: 9.71 ET, 141.42 MPH, 1.40 60' , 610 RWHP Mustang Dyno
www.speartech.com
Joined: Nov 2001
Posts: 1,707
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From: Anderson, Indiana
If you really want the dash light to work, you would need to break the connection from the PCM and then wire the light in as described above. On the 99 and up, it will set a code, but won't affect anything.
No, the other 3 connections are for other functions, that aren't used in this application.
No, the other 3 connections are for other functions, that aren't used in this application.
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91 Z28 LS2 408CI, LS9 Supercharger, LPE GT7 cam, Yank3000, 3450 raceweight.
Latest numbers: 9.71 ET, 141.42 MPH, 1.40 60' , 610 RWHP Mustang Dyno
www.speartech.com
91 Z28 LS2 408CI, LS9 Supercharger, LPE GT7 cam, Yank3000, 3450 raceweight.
Latest numbers: 9.71 ET, 141.42 MPH, 1.40 60' , 610 RWHP Mustang Dyno
www.speartech.com
How would an ammeter be configured in this situation (with my 2000 harness)? My '70 gauge measures current not voltage. For now I want to stick with stock gauges, so if there's a way to wire it up so that I have an idea that the charging curcuit is working, I would like to do it. The original alternator had three wires in addition to the big wire going to the battery. (I'm not sure which one does what though...)
On The Tree
Joined: May 2004
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From: London, UK
What are the other functions that the 3 unused connections are meant for?
I may have misinterpreted, but the single wire that runs from my PCM to the alternator is the exciter wire, yes? To cut this wire and connect a bulb into it would mean that the bulb would be turning on all the time, wouldn't it?
I may have misinterpreted, but the single wire that runs from my PCM to the alternator is the exciter wire, yes? To cut this wire and connect a bulb into it would mean that the bulb would be turning on all the time, wouldn't it?
Joined: Nov 2001
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From: Anderson, Indiana
No, the bulb wouldn't be on all of the time unless there is a problem with the alternator. The bulb comes on with the key on but as soon as you start the engine and current starts to flow in the alternator, you have the equivalent of 12 volts on BOTH sides of the bulb, so it goes out. If you have certain diode or regulator failures, the light will come on, warning you of a problem.
The other terminals are not used in this application, and you shouldn't try and use them for anything, but they are:
S = the Sense lead. used to sense the charging voltage. It's done internally on our alternator.
L = Lamp terminal. This is the one used to turn on the regulator either thru a lamp, a resistor, or let the PCM do it on 99 and up applications.
F = Field terminal. Can be used to control the output by controlling the field voltage. Some applications let the PCM control this terminal.
I = I forget what this one even does
. I don't think any applications use it that I know of.
The other terminals are not used in this application, and you shouldn't try and use them for anything, but they are:
S = the Sense lead. used to sense the charging voltage. It's done internally on our alternator.
L = Lamp terminal. This is the one used to turn on the regulator either thru a lamp, a resistor, or let the PCM do it on 99 and up applications.
F = Field terminal. Can be used to control the output by controlling the field voltage. Some applications let the PCM control this terminal.
I = I forget what this one even does
. I don't think any applications use it that I know of.
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91 Z28 LS2 408CI, LS9 Supercharger, LPE GT7 cam, Yank3000, 3450 raceweight.
Latest numbers: 9.71 ET, 141.42 MPH, 1.40 60' , 610 RWHP Mustang Dyno
www.speartech.com
91 Z28 LS2 408CI, LS9 Supercharger, LPE GT7 cam, Yank3000, 3450 raceweight.
Latest numbers: 9.71 ET, 141.42 MPH, 1.40 60' , 610 RWHP Mustang Dyno
www.speartech.com
