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Curtis B.
Curtis B., Technician
Category: Medium and Heavy Trucks
Satisfied Customers: 28897
Experience:  Technician turned service manager on multiple lines of trucks and engines, used in industry.
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What are the S and R terminals connected to? A few days,

Customer Question

What are the S and R terminals connected to?
JA: I'll do all I can to help. How long have you been dealing with this?
Customer: A few days, since I got a new alternator. I can't get it to work. Apparently it is designed for a plug that has an R and an S terminal
JA: Do you plan on doing the work yourself?
Customer: Yes
JA: Anything else we should know to help you best?
Customer: I odn't think so
Submitted: 2 months ago.
Category: Medium and Heavy Trucks
Expert:  centralappliance1 replied 2 months ago.

Hello, one minute while I get some information together.

Expert:  centralappliance1 replied 2 months ago.

What is the make and model of the unit?

Customer: replied 2 months ago.
It's a 12v 80A unit for diesel engines--I don't know moe than that right now.
Expert:  centralappliance1 replied 2 months ago.

Let me see if another expert can help one moment

Expert:  Curtis B. replied 2 months ago.

S is sensor, R is for relay. Alternator has to be energized to start charging, when key is turned on, that should be the sensor. It would have 12 volts , when key is turned on. The relay is for battery light circuit. Need the alternator number to see the exact wiring diagram.

Expert:  Curtis B. replied 2 months ago.

I see question is still open, please use the 5 star rating system to close the question and get me credit! Thanks!