SI to CS144 Conversion
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Melting Slicks
Joined: Feb 2001
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From: TEXAS - you mean there are other states?
Thanks - can you repost that in better resolution? That looks like a good chart. Does it indeed say "I" Ignition terminal? What about the "F" Field terminal?
Thread Starter
Melting Slicks
Joined: Feb 2001
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From: TEXAS - you mean there are other states?
I found an article that went into the fact of different terminal codes and related different regulators:
10. The CS terminals are designated as follows:
P-Terminal: The Pulse/Phase terminal can provide a 12V square wave to determine alternator speed, used by some Electronic Control Modules or vehicle computers. Connects to the stator. Some ICU’s monitor this signal and adjust engine parameters accordingly.
L-Terminal: This terminal is connected to the “Low” side of the warning lamp, with the lamp’s “High” side being fed by the ignition circuit. Some regulators require a 35-ohm resistance inline with this circuit if no lamp is used otherwise alternator damage may ensue. Some applications have a resistor connected in parallel to the lamp in case the lamp bulb opens up and burns out. The resistor will be there to provide a path for current and voltage. Some vehicles supply a 5Vdc reference to this terminal from their ECU or Computer; other vehicles don’t, so be aware of the various models of regulators. Other regulators may be tested by application of a 50-Ohm pull-up resistor to connect the L-Terminal to the 12Vdc source, I believe that any resistance between 35 Ohms (5-Watt resistor) and 500 Ohms (1/2 Watt resistor) can be used safely.
F/I-terminal: has several duties depending on the specific regulator, some regulators have a resistor that is internally connected between the Field and Lamp terminal. Other regulators use the F/I terminal to provide field duty cycle information to the vehicles Electronic Control Module or computer. These regulators are not interchangeable, but for our Jeeps, it hardly matters. For ECM related vehicles it can be of paramount importance. If the alternator that is selected comes from a vehicle that only uses the I-Terminal then the wiring may simply require a wire from an ignition source in order for the alternator to operate correctly.
S-terminal: This is a heavier gauge terminal spade lug that is connected to the battery. This terminal is the “Sense” circuit and monitors battery charge. The S-terminal on the CS-130 regulator is larger than the other three terminals.
The CS-130D Alternators have the following connections…NOTE: All of the Terminals on the CS-130D regulators are the same size.
P-Terminal: Provides a 12Vdc square wave as in the CS-130 application.
F/I-Terminal: It gets a bit tricky here, as some applications do not incorporate a lamp circuit. In vehicle applications of the “no lamp” kind, this terminal is connected to the Ignition Switch, and an internal resistor is used to limit current and voltage. Other regulators use this terminal as an output and refer to this pin as a Field Terminal, as such, it provides an output that is proportional to the field duty cycle of the alternator to an a vehicles ECM. The ECM now has an input to sense alternator loading and engine loading, and can increase/decrease engine speed accordingly. Here is an important consideration, since the regulators on CS-130D type alternators have these two different types of regulators (F-Type or I-Type) they cannot be interchanged. I-Type regulators use the F/I-Terminal as an input and this can simply be an ignition source 12Vdc voltage that the alternator uses; F-Type regulators use the F/I-Terminal as an output (this ion is a signal that is provided to the vehicle computer and the computer uses it to monitor the field intensity of the alternator as an input. If you supply a 12Vdc signal to this input, you may very well ruin the alternators regulator.
L-Terminal: This is the lamp terminal and operates in the same manner as the CS-130 lamp circuit above. It is of interest to note that some applications use the ECM to send the L-Terminal a signal (5Vdc reference), and the F-Terminal responds with a signal sent to the ECM, in this application the ECM and the Regulator form a “closed loop” to control engine loading and alternator output.
S-Terminal: This is the “Sense” terminal and is connected to the battery. It senses the voltage level of the battery and feeds the regulator circuit this reference so that the regulator can adjust the Pulse Width Modulation to control the alternators output. The S-terminal on the CS-130D regulator is the same size as the other three terminals, unlike that of the CS-130.
Since these CS-series regulators are now essentially an electronic computer chip, so always disconnect the battery before servicing, and do not EVER remove the battery cable when the engine is running. If you simply must do this, you may have just destroyed the regulator’s computer chip. You must really begin to think of these alternators as computers, and treat them with the respect that you might a laptop computer.
CS-Series alternators use diodes within the rectifier plate known as avalanche diodes. Original equipment designs use avalanche diodes in both positive and negative plates with a forward voltage of 0.9V @ 100 Amps and an avalanche voltage of less than 40 volts, in the better-designed regulator/rectifier units.
There is an up and a down side to using these devices. On the up side, they prevent damage and surges, current spikes, and such from reaching sensitive electronic equipment inside the cab and under the hood.
On the down side, due to the nature of their operation, their lifespan is not as long as the earlier diode trio’s used in 10/12-SI alternators. Still, many years of service can be expected, just not decades as in earlier alternators, I believe that the service life of the CS-series alternators is somewhere around 80,000 to 100,000 miles depending upon specific model number (CS-121, CS-130, CS-130D and CS-144.
10. The CS terminals are designated as follows:
P-Terminal: The Pulse/Phase terminal can provide a 12V square wave to determine alternator speed, used by some Electronic Control Modules or vehicle computers. Connects to the stator. Some ICU’s monitor this signal and adjust engine parameters accordingly.
L-Terminal: This terminal is connected to the “Low” side of the warning lamp, with the lamp’s “High” side being fed by the ignition circuit. Some regulators require a 35-ohm resistance inline with this circuit if no lamp is used otherwise alternator damage may ensue. Some applications have a resistor connected in parallel to the lamp in case the lamp bulb opens up and burns out. The resistor will be there to provide a path for current and voltage. Some vehicles supply a 5Vdc reference to this terminal from their ECU or Computer; other vehicles don’t, so be aware of the various models of regulators. Other regulators may be tested by application of a 50-Ohm pull-up resistor to connect the L-Terminal to the 12Vdc source, I believe that any resistance between 35 Ohms (5-Watt resistor) and 500 Ohms (1/2 Watt resistor) can be used safely.
F/I-terminal: has several duties depending on the specific regulator, some regulators have a resistor that is internally connected between the Field and Lamp terminal. Other regulators use the F/I terminal to provide field duty cycle information to the vehicles Electronic Control Module or computer. These regulators are not interchangeable, but for our Jeeps, it hardly matters. For ECM related vehicles it can be of paramount importance. If the alternator that is selected comes from a vehicle that only uses the I-Terminal then the wiring may simply require a wire from an ignition source in order for the alternator to operate correctly.
S-terminal: This is a heavier gauge terminal spade lug that is connected to the battery. This terminal is the “Sense” circuit and monitors battery charge. The S-terminal on the CS-130 regulator is larger than the other three terminals.
The CS-130D Alternators have the following connections…NOTE: All of the Terminals on the CS-130D regulators are the same size.
P-Terminal: Provides a 12Vdc square wave as in the CS-130 application.
F/I-Terminal: It gets a bit tricky here, as some applications do not incorporate a lamp circuit. In vehicle applications of the “no lamp” kind, this terminal is connected to the Ignition Switch, and an internal resistor is used to limit current and voltage. Other regulators use this terminal as an output and refer to this pin as a Field Terminal, as such, it provides an output that is proportional to the field duty cycle of the alternator to an a vehicles ECM. The ECM now has an input to sense alternator loading and engine loading, and can increase/decrease engine speed accordingly. Here is an important consideration, since the regulators on CS-130D type alternators have these two different types of regulators (F-Type or I-Type) they cannot be interchanged. I-Type regulators use the F/I-Terminal as an input and this can simply be an ignition source 12Vdc voltage that the alternator uses; F-Type regulators use the F/I-Terminal as an output (this ion is a signal that is provided to the vehicle computer and the computer uses it to monitor the field intensity of the alternator as an input. If you supply a 12Vdc signal to this input, you may very well ruin the alternators regulator.
L-Terminal: This is the lamp terminal and operates in the same manner as the CS-130 lamp circuit above. It is of interest to note that some applications use the ECM to send the L-Terminal a signal (5Vdc reference), and the F-Terminal responds with a signal sent to the ECM, in this application the ECM and the Regulator form a “closed loop” to control engine loading and alternator output.
S-Terminal: This is the “Sense” terminal and is connected to the battery. It senses the voltage level of the battery and feeds the regulator circuit this reference so that the regulator can adjust the Pulse Width Modulation to control the alternators output. The S-terminal on the CS-130D regulator is the same size as the other three terminals, unlike that of the CS-130.
Since these CS-series regulators are now essentially an electronic computer chip, so always disconnect the battery before servicing, and do not EVER remove the battery cable when the engine is running. If you simply must do this, you may have just destroyed the regulator’s computer chip. You must really begin to think of these alternators as computers, and treat them with the respect that you might a laptop computer.
CS-Series alternators use diodes within the rectifier plate known as avalanche diodes. Original equipment designs use avalanche diodes in both positive and negative plates with a forward voltage of 0.9V @ 100 Amps and an avalanche voltage of less than 40 volts, in the better-designed regulator/rectifier units.
There is an up and a down side to using these devices. On the up side, they prevent damage and surges, current spikes, and such from reaching sensitive electronic equipment inside the cab and under the hood.
On the down side, due to the nature of their operation, their lifespan is not as long as the earlier diode trio’s used in 10/12-SI alternators. Still, many years of service can be expected, just not decades as in earlier alternators, I believe that the service life of the CS-series alternators is somewhere around 80,000 to 100,000 miles depending upon specific model number (CS-121, CS-130, CS-130D and CS-144.
Thread Starter
Melting Slicks
Joined: Feb 2001
Posts: 2,608
Likes: 3
From: TEXAS - you mean there are other states?
I went to the auto parts this morning and checked part # 5328PT. It had no resistance in the wire either. Just fyi - the wire colors on 5328PT were blue and green.
So - Alan - can you verify what terminal your GM wire goes to and if it has resistance and how much? thanks
btw - I ran my 8 gauge wire from the starter terminal to the alternator area. It looks really nice and follows the engine harness perfectly. All I have left to do is to solder a connector at the alternator.
Alan - what did you do at the alternator connector boot - how did you compensate and cover the additional 8 gauge wire.
So - Alan - can you verify what terminal your GM wire goes to and if it has resistance and how much? thanks
btw - I ran my 8 gauge wire from the starter terminal to the alternator area. It looks really nice and follows the engine harness perfectly. All I have left to do is to solder a connector at the alternator.
Alan - what did you do at the alternator connector boot - how did you compensate and cover the additional 8 gauge wire.
Thread Starter
Melting Slicks
Joined: Feb 2001
Posts: 2,608
Likes: 3
From: TEXAS - you mean there are other states?
Well – just a quick update…..
I tried every harness adapter known to man:
Lectric Limited
Pico 5327PT
GM 12102921 (8078)
None worked…..
So from the research, I saw certain articles that designated which alternators were appropriate for this conversion. One mentioned AC/GM 10463338, or Ultima 01-0594 (1993 Cadillac Fleetwood Brougham). I had been using an Ultima 01-0580 (1993 Coupe de Ville). Once I changed to this alternator and tried my GM adapter pigtail – it worked !!!! I do not know the difference – but just shake my head from all the running around I have done.
I did call PowerMaster (as that will be my next replacement since these Ultimas are crap) and they said the one they recommend for that application is #7805 (140amp) or #47805 (200amp). Either will need pulley # 111.
On the rubber cap that goes over the Charging wire at the alternator, I was able to ‘stretch’ the rubber cap to fit over the new additional 8 gauge wire/connector. It just took a bit of patience. It is a tight fit – but does work.
I tried every harness adapter known to man:
Lectric Limited
Pico 5327PT
GM 12102921 (8078)
None worked…..
So from the research, I saw certain articles that designated which alternators were appropriate for this conversion. One mentioned AC/GM 10463338, or Ultima 01-0594 (1993 Cadillac Fleetwood Brougham). I had been using an Ultima 01-0580 (1993 Coupe de Ville). Once I changed to this alternator and tried my GM adapter pigtail – it worked !!!! I do not know the difference – but just shake my head from all the running around I have done.
I did call PowerMaster (as that will be my next replacement since these Ultimas are crap) and they said the one they recommend for that application is #7805 (140amp) or #47805 (200amp). Either will need pulley # 111.
On the rubber cap that goes over the Charging wire at the alternator, I was able to ‘stretch’ the rubber cap to fit over the new additional 8 gauge wire/connector. It just took a bit of patience. It is a tight fit – but does work.
Le Mans Master
Joined: May 2006
Posts: 9,993
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From: League City Tx
If you are looking for ideas on an alternator, this is the one I just switched to....
http://store.alternatorparts.com/140...lternator.aspx
I was also using the Ultima CS144 from OReilys for a 97 Caddy Deville, first one was a reman, it charged but was not charging to my satisfaction....with the headlights, fan, AC, high beams, brake light on and idling at 800rpms, I was only getting 12.5-12.6v at the battery.....going down the road was like 13.2v.
Then I switched it for an Ultima BRAND NEW alternator....It basically had the same voltage output...maybe .1 better...
I took it back and got a full refund and ordered the CS144HD from Quickstart. It is a new alternator that they build from original AC Delco parts. It also has a heavy duty 200amp bridge rectifier, HD voltage regulator. I got that one on and at full electric load, (H/L beams, AC, FAN, brake lights, stereo w/ amp etc) idling at 800rpms gets me 13.6-13.7v at the battery.... Most of the time it stays in the 14.0-14.2 range with the headlights/fan on only.....Basically it is 1.0v better everywhere and it costs the same....I think my total shipped was $206.....the Oreilys Ultima was $205.....
I have put about 500-600 miles on it in the last month and its ticking along perfectly....
http://store.alternatorparts.com/140...lternator.aspx
I was also using the Ultima CS144 from OReilys for a 97 Caddy Deville, first one was a reman, it charged but was not charging to my satisfaction....with the headlights, fan, AC, high beams, brake light on and idling at 800rpms, I was only getting 12.5-12.6v at the battery.....going down the road was like 13.2v.
Then I switched it for an Ultima BRAND NEW alternator....It basically had the same voltage output...maybe .1 better...
I took it back and got a full refund and ordered the CS144HD from Quickstart. It is a new alternator that they build from original AC Delco parts. It also has a heavy duty 200amp bridge rectifier, HD voltage regulator. I got that one on and at full electric load, (H/L beams, AC, FAN, brake lights, stereo w/ amp etc) idling at 800rpms gets me 13.6-13.7v at the battery.... Most of the time it stays in the 14.0-14.2 range with the headlights/fan on only.....Basically it is 1.0v better everywhere and it costs the same....I think my total shipped was $206.....the Oreilys Ultima was $205.....
I have put about 500-600 miles on it in the last month and its ticking along perfectly....
Last edited by ajrothm; Nov 10, 2010 at 03:48 PM.
Le Mans Master
Joined: Jan 2001
Posts: 6,746
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Here: do this check to find your pigtail
Try using this to figure out your adapter. Follow the guidance as written. Worked the first time for me. Go to your local parts store and get the equivalent pigtail part number:
The site below tells you how to figure out which adapter to buy for your CS-144 tie in to your 12SI: I also added the key paragraph below in case you cannot open it.
http://www.corvetteactioncenter.com/...red_parts.html
"If you are unsure which adapter to use, measure the resistance of the exciter line. Disconnect the positive battery cable and the alternator plug. Connect an ohm meter between the #1 terminal on the plug end of the alternator harness and the end of the positive battery cable. Turn the ignition key to the "on" position and read the ohmmeter. If resistance is less than 35 ohms, use adapter #8078. If it’s between 35-350 ohms, use #8077. If it’s more than 350 ohms, you have excessive resistance somewhere in that circuit which needs to be repaired, first."
The site below tells you how to figure out which adapter to buy for your CS-144 tie in to your 12SI: I also added the key paragraph below in case you cannot open it.
http://www.corvetteactioncenter.com/...red_parts.html
"If you are unsure which adapter to use, measure the resistance of the exciter line. Disconnect the positive battery cable and the alternator plug. Connect an ohm meter between the #1 terminal on the plug end of the alternator harness and the end of the positive battery cable. Turn the ignition key to the "on" position and read the ohmmeter. If resistance is less than 35 ohms, use adapter #8078. If it’s between 35-350 ohms, use #8077. If it’s more than 350 ohms, you have excessive resistance somewhere in that circuit which needs to be repaired, first."
Last edited by carriljc; Dec 21, 2013 at 10:05 PM. Reason: fix link
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