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**dmjlambert** · 01-19-2019, 12:05 AM

Since the donor vehicle didn't use the S lead, it is possible the alternator doesn't need it to work, especially in the 1987 truck. In your simpler wiring in the older truck where you are moving it to, it is possible connecting S anyway will better control the alternator output. To do that you would need to buy another plug that has the connector in the S position, or buy one of those adapters like VetteVet gives the part number for.

The American Autowire pdf I gave the link to they say you just need the L wire connected with a resistor as shown in their adapter diagram. That you can do with the donor plug, you just don't need to connect the red/black-stripe F wire to anything.

I'll agree this stuff is confusing. I bought a CS144 alternator for a 1993 Chevy truck, but I bought it new from the parts store instead of getting it with the plug out of a donor truck. So I don't have the benefit (or added confusion) of knowing what terminals were used in the 1993 application, but I just wired it using VetteVet's guidance in the many forum posts on this subject. I used the L and S terminals as shown in VetteVet's diagram above. Works great!

01-19-2019, 12:05 AM	#8
dmjlambert Senior Member Join Date: Apr 2016 Location: Cypress, TX Posts: 3,563	Re: Alternator wiring GM CS130 Since the donor vehicle didn't use the S lead, it is possible the alternator doesn't need it to work, especially in the 1987 truck. In your simpler wiring in the older truck where you are moving it to, it is possible connecting S anyway will better control the alternator output. To do that you would need to buy another plug that has the connector in the S position, or buy one of those adapters like VetteVet gives the part number for. The American Autowire pdf I gave the link to they say you just need the L wire connected with a resistor as shown in their adapter diagram. That you can do with the donor plug, you just don't need to connect the red/black-stripe F wire to anything. I'll agree this stuff is confusing. I bought a CS144 alternator for a 1993 Chevy truck, but I bought it new from the parts store instead of getting it with the plug out of a donor truck. So I don't have the benefit (or added confusion) of knowing what terminals were used in the 1993 application, but I just wired it using VetteVet's guidance in the many forum posts on this subject. I used the L and S terminals as shown in VetteVet's diagram above. Works great!