Re: 1 wire alternator confusion

Posted by BigKev On 2022/12/15 9:50:44

One note on running a 3-wire without anything attached to the voltage sensing terminal, if that is not hooked up, that alternator is going to be outputting at max all the time, which can overcharge your battery. You at least want to pigtail that terminal back to the bat terminal on the Alt so it can read the bat voltage.

Usually, in GM products where that 10Si was used, the voltage sensing terminal was connected to a wire that was connected near a junction point in the main harness. This was done so its reference voltage was read nearer the load center vs. right off the alternator output.

If you don't have the terminal connected, you're going to see very high voltage, which may lead to a cooked battery or the regulator in the alternator having a shorter-than-expected life expectancy.