Ordered the S383 from Rock Auto. Will take another week to get here.

 

The CS144 doesn't need the sense terminal connected. It only needs the L terminal to excite it and get it to start charging when the engine is started. So, unplug that harness. Connect the ground wire of a test light to the power stud on the back of the alternator. Touch the probe of the test light to the alternator case to make sure it is working. Start the engine. Touch and temporarily hold the probe of the test light to the L terminal. The light should go out and the alternator should start charging. You don't need to hold the light connected to keep it charging once the light goes out.

If the test light doesn't go out then the alternator is bad.

 

Thank you. This differs significantly from other info in this thread and online, but I have faith and will give this a try. If I’m understanding you correctly, I’m essentially using the voltage light to provide power from the + of the alternator to the L terminal for a brief second which starts the alternator charging. If that works, then it’s figuring out how to provide that power from the proper line in the car. Only 1 wire needed. NO wire into the S terminal at all, at any time?

Is a resistor required?

 

Just did an engine off quick check with a voltage light (residential wire type, confirmed works at 120 volts). I get NO light when checking across the positive pole of the alternator and the case. A multimeter shows 12VDC. Alternator was tested yesterday and PASSED. Should I question that passing result? Do I need an automotive test light for lower voltage?

A picture is worth 1000 words. This is from Positive pole on alternator to the case, key on or key off (not start). Light is OFF. Same test shows 12VDC with a multimeter.

 

Yes, just one wire to excite the alternator is all it needs. Lots of GM came wired that way from the factory. I've been running one for years with just a single wire to it, no S terminal connection.

The bulb in the test light is the resistor. No resistor is needed with a bulb. You need a bulb with a filament. I suspect that test light is a neon bulb.

Out of curiosity, does your alternator have P L I S or P L F S as the 4 terminals?

 

Thanks. Looking for a bulb style in the tool box and will test again. Alternator is PLFS. Therefore the newer S383, ACDelco 8077 discussed in this thread is WRONG (note the early conversation about voltage light and resistance indicating I should connect to F). The pins align to _ _ F S while the ACDelco 8078 (which ive had in the car previously with better results than the 8077) is _ L _ S.

If im going to connect to only the L (using the 8078 harness), do I need a 150ohm resistor inline? Do i need to rev up the engine to make sure it kicks on the alternator?

 

There is so much misinformation about the CS144 alternator wiring on the internet that you can hardly believe any of it. No wonder you are totally confused.

You can connect ignition switched directly to the I terminal if you had the PLIS terminals. Don't connect directly to the F terminal. You don't have the PLIS version so you can't do it that way.

Any small 12V bulb will work. Got a marker or tail light bulb in a socket or a bulb and a piece of wire?

To use a bayonet bulb (bulb with the metal ground shell and center power pin) and a piece of wire strip both ends of the wire and then hold the bulb between your fingers also pinching the wire against the outer ground shell. Then, touch the middle pin to the power stud and the other end of the wire to the L terminal at the same time.

 

There is a lot of confusion about the CS144 wiring . I'm not sure where it originated, but there is widespread information that ranges from being inaccurate to flat out wrong when you try to search how to wire one of these alternators.

Lots of sources say to connect the S terminal to the big output stud. That is totally pointless on a CS144 and serves no purpose since the alternator uses the output stud as the sensing source by default. You only need to use the S terminal if you want to connect it somewhere further into the circuit so the alternator can compensate for voltage drop in the charging wire. For example, run the charging wire to a terminal block where your electric fans are connected then also connect the S terminal there.

Lost of sources say the L terminal needs no resistor or light. That is wrong, it is only the I terminal that can be connected without a light or resistor, not the L or F terminals. I've seen so many diagrams with the L and I or L and F terminal and saying both are for no light. Then, others have the L mixed up with the I or F and say it's no light and the other one is.

You will also find lots of info about needing a resistor in series with your indicator light. This isn't necessary. The little dash indicator light gives plenty of resistance for the alternator.

Here, this site explains the CS wiring well. Scroll down to the section "CS Series / 4-terminal Alternators"

https://www.pirate4x4.com/threads/12...#post-44988321

The PLIS drawing is a little confusing because there is a shorted resistor connected to the I terminal. This is supposed to be meaning that the I terminal can be directly connected or use a resistor.

 

Seems to be solved. It was stupidly simply. Added a 150ohm resistor to the 8078 harness ive had on the car all along. Fired up and have 13.7 on the computer ECU. This was easier than the bulb trick, lol. Wouldve used that if trouble shooting was needed. Now to go get the ECU setup properly and fingers crossed it stays.

I presume I was burning out alternators without the resistor in place. It would work fine for a while, then car would act terribly the next trip out.

Final wiring pic:

 

Now upgrade the charge wire.

 

Will do. I can simply cover this up and run a parallel line to the starter lug? I’m adding the 175 amp block fuses to the battery positive connections.

 

Richard... sounds like YOU need to put a "kit" together with connectors, fuses, wiring and alternator... plug n play and DONE.