1999 Mazda Protege alternator not charging battery

1999 MAZDA PROTEGE
975,000 MILES • 1.6L • 4 CYL • 2WD • AUTOMATIC
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KINKOU
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My Mazda is not allowing the alternator to charge the battery. Both have been replaced and read as good, but still the battery will not charge. Leads, etc all changed (including Main Computer Relay in fuse box). When you turn the key (not start just turn key), a strange "whir-whir" sound comes (kinda reminds me of the sound my son's old cd player makes when changing cds BUT I don't have a cd player in car). Do you have any ideas?
Apr 7, 2015 at 4:42 AM
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JACOBANDNICKOLAS
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When the car is running, is there any change in the battery voltage? If not and all the wiring is good, I would suspect there is an issue with the PCM. The PCM on this vehicle functions as a voltage regulator.
Apr 7, 2015 at 5:05 AM