The Stovebolt Site Forums The Shop Area The Electrical Bay Alternator question

Re: 10si or 12si GM Alternators

I've long suspected that the "sense" wire pin (pin #2 on the slip on plug) has an internal connection to the output terminal of the alternator. The connection would have to have more resistance that a direct short, lets say 100 ohms just for laughs. That way if a real sense wire was connected to pin #2 the sense wire voltage would be passed to the fairly high impedance voltage regulator sense input in the alternator. without regard to the voltage on the terminal. But if no wire were connected to pin 2, the voltage from the output terminal would find its way through the 100 ohms (or whatever) of the internal resistance and into the voltage regulator.

Question: What do you think?

Question 2: Could I test my theory by ...
... A. Removing the sense wire from my own 10si 3 wire alternator, start the truck and see what happens?
... B. Removing the sense wire and the output wire, then measuring resistance between the 2 points on the alternator?