03 mazdaspeed voltage regulator

[lalatoyab4]

So we have replaced alternator and new battery. Battery light still comes on I've been told voltage regulator . I've read so many things I'm quite confused. Is there a voltage regulator I can replace or is it the pcm. Any help would be appreciated thanks.

 

[hornsfan10609]

Voltage is regulated in the PCM on the Protege.