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Trouble Getting Alternator to Charge

Practical Motorsport Wiring - Club Level

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I recently rewired my drag car from scratch because it was a really old build and had poor wiring. After taking some classes here everything worked, except the alternator. The Alternator was charging before, so I assume it’s something with my wiring.

I have a large, 4 gauge, running directly to my battery and then have a 12v exciter wire that I have plugged into the port closest to B. I’m not sure if I have to send battery voltage to the other side, it isn’t labeled, or if im doing something else wrong.

Attached is a picture of the rear of the alternator

Any help is appreciated.

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It would help a lot if you actually told us the make and model of the alternator and vehicle, there are quite a few different configurations.

For example, similar sockets to that may be the battery side - the scaling isn't clear - with one battery terminal (B) and the other a ground terminal, if it's a small socket, it could be a battery reference and warning light feed from the ignition. Or they could be quite different to either of those.

There is also a smallish chance you've already 'blown' the regulator or rectifying diodes so it isn't working, period.

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