Dodge Cummins does not charge

1990 Dodge Cummins, 111,000 miles - does not charge, is not putting out.
Installed new Chrysler alternator from NAPA and isolated field electronic regulator. Parts store (NAPA) checked the alt., said it is OK. Cleaned all ground/hot connections. Battery is 12.6 v. Have 12 v power at reg. and alt. Key “on” and both field pins hot (12v). Any ideas, suggestions? Thanks.

Does the “charge” or “battery” light icon on your dash light up when the key is in the on position? If the light is not on because of a blown bulb the alternator will not charge.

There is no charge or battery light.
Anyway, I took off the new, made in China, regulator and replaced it with an old, made in USA regulator that I’m borrowing from a friend. I fired it up, the volts went immediately from 12.7 to 14. Everything is good! Too bad there doesn’t seem to be any way to test a regulator, even a new one, except for putting it in to see if it works. Or not.

Glad you found the problem. Unfortunately, most of the made in China products are cheap knockoffs of real parts. I hope that “made in China” products go away very soon but I think it’s just wishful thinking on my part.