Alternator not charging.

Vlad1 wrote: I have a question.
It looks like it is equally likely that I keep getting defective parts or units as well as I get undamaged units/parts, but destroy them by improper testing technique or some sort of undiagnosed failure at car's electrical system.

My money is on defective parts. But I've been wrong before! A coworker went through the same hassles with a 2012 Grand Caravan recently. Took four parts store reman alternators before we found one that charged correctly. We all know what NEW stands for. :silly:

Is there any way to diagnose the supplied voltage to the pigtail connector while the alternator is off car? Any particular sense to measure the voltage on B/W and B/G wires of the pigtail connector while the alternator is not installed?

You absolutely can test these circuits with the alternator out of the car. As we know, white/green is from a fuse, and should support at least a few amps of current flow. If you want to be 200% certain about this circuit, you can load it with a headlight bulb. For example, I have a 9006 bulb and pigtail for exactly this purpose. The low beam part of the bulb draws around 3.5A, and the high/low together draws closer to 8A.

Using the white/green as the power, jumper the other side of the bulb to ground. The bulb should light brightly. If it does, you know that wire is capable of carrying current.

The white/black can be tested just by having the key on and connecting the jumper to ground and observing the battery light on the dash. If it lights, your circuit is good.

What would be theoretical way to damage the alternator by testing it?

I don't know? :silly: I've never done bench testing this way before, so I'm honestly not sure if damage is possible!

Thank you,
great idea with the light bulb. Something I can do while waiting for a new alt-r to arrive. I contacted the seller of the regulator, they responded right away. They will be able to RMA it, but they are sure it was working as they tested it. The later part puzzled me as I was looking for any ways to bench test the voltage regulator and could not find it.
OK, maybe I'm overthinking of me killing the electronics by applying the current from the AA and standard 9V batteries...
That story about 4 alternators not working in a row gives me hope as well as makes me desperate in some sense (: