Denso alternator wiring issue?

Good evening, Having an issue with a new build here. 1970 Challenger, 440RB, Sniper injection. I purchased the AR alternator brackets, Denso Alt connector, new Denso alternator. Simple 3 wires to hook up (or so I thought). BAT lug going to stud on starter relay, along with wire from ammeter , blue wire is also directly to stud on relay, red not used, green has 12v key on/start position. I'm getting no charge, only 12v bat showing on volt meter and same on Sniper's hand held. I could have a bad alternator, but it is new, so I doubt it. What am I not doing correctly? Any help is appreciated! Thanks, Jeff

pay attention to the terminal position on the back of the alt. double check that.
also verify that you are actually getting 12v to the plug with the key on.

These days, something being new doesn't necessarily mean its good. The next question is, was it brand new, or rebuilt new? Not that it makes much difference these days, the quality of all automotive parts has gone down the tubes the last 4-5 years. Gene

If the Denso is brand new and sealed up, very doubtful it is bad.. Possible but not likely..
I steer clear of all the AutoZone, Advance, O'Reily mastercraft specials, even though they may have a life-time warranty. To me, my time & labor is far more valuable to save a few $, do the job once and right..


Just my $0.02

Mine wouldn't charge until I hooked up the red wire as well. This is all from memory, but if I am recalling correctly - In stock systems positive from the battery goes to a split circuit with a resistor on one path and a lamp on the other, and then to the red wire terminal on the alt. According to the Toyota tech that helped me out, this is also the exciter wire. I skipped the whole split circuit bit and ran a wire from switched source under the dash and back to the alt. Alternator setup worked fine once I did that.

Not an expert, just the best memory of my experience getting the setup working. Should be easy to test out for you.

Best of luck to you.

This is why I only use a genuine Denso starters and alternators. They last forever on a daily driver so they do great on our cars I run the sense wire to the relay and the main 10 gauge wire to the battery positive terminal on my shut-off switch.
Gus

This is the best article I've ever found on wiring Denso's.

Denso Wiring

Thanks guys! I got back to it today (finally!) Started the car, it's charging normal at 14.3v! Who knows! My tester, volt gauge, sniper hand held all read 12.3v the other day, now all reading 14+. Now I did not hook up the red wire (gauge wire) at all, just taped it off. Right or wrong? Right now, I'm gonna consider it working. Take care, Jeff