More help please on CS TO SI

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Jgonick

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I went through the resistor issue also a year ago with my SI alt. I don't have an idiot light. I didn't realize the BRN wire becomes BRN/WHI (which is a resistance wire) with gauges.
 

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I went through the resistor issue also a year ago with my SI alt. I don't have an idiot light. I didn't realize the BRN wire becomes BRN/WHI (which is a resistance wire) with gauges.

You just answered half of my decade long mystery, thank you!
 

mavtricks71

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The terminals on a CS are PLFS or PLIS. which do you have?

The Ac delco PT2145 should work, but you might have to move the yellow wire over one depending on the alternator's terminals & setup.

EDITED: After looking at the adapter again- It should work no matter what. It appears to have the a resistor in the yellow "Lamp" wire.
I believe thats a Diode in the wire not a resistor?
 

mavtricks71

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I went through the resistor issue also a year ago with my SI alt. I don't have an idiot light. I didn't realize the BRN wire becomes BRN/WHI (which is a resistance wire) with gauges.
So I wouldnt need the resistor added to my PT2145 plug since I have a voltage gauge in my dash correct?
 

Jgonick

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So I wouldnt need the resistor added to my PT2145 plug since I have a voltage gauge in my dash correct?
That is what I believe - you should be good as long as a PO didn't mess with the BRN/WHT wire. However, if your CS alternator has PLIS connection, you could just move the yellow (BRN) wire over to the "I" slot. -Then it wouldn't matter either way.


Updated Info: SI and CS requirement looks different.

SI alternator says 10 ohm rated at 6 watts or more- CS alternator says 35 ohm at 5 watts to 500 ohm Using "L" terminal.

UPDATE: Also -Ac delco PT2145- I looked at reviews online- it is a resistor- So it looks like it should work.
 

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82BBC20

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82sbshortbed that’s how I wired mine, I think I used a tag light socket & bulb. Got my wiring info from the alternator bible and I’ve had no issues!
 

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