@derrick8834 have you scanned the OBD_II. If the PCM receives either under or over voltage, it will pop a code. Something like a P0562 or P0563
The amount of DC current produced by the generator is controlled by EVR circuitry contained within the PCM. This circuitry is connected in series with the generators second rotor field terminal and its ground. So yes, it is possible that this is strictly PCM related.
Since this is a new alternator, we are going by the assumption that the output voltage is proper. You may need this Charging System Besides checking all the wiring and the bulkhead connector, check fuse F22 in the power distribution center. There is also a fusible link in the wire (Black/White) from the alternator to the battery. See if that has continuity
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