1999 Subaru Wagon

1999 SUBARU WAGON
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NICK MAPLE
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1999 Subaru Wagon

On engine start up what induces an alternator's magnetism?
Apr 2, 2010 at 10:27 AM
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RACEFAN966
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It don't work that way. It takes 12 volts from the battery to excite the alternator if there isn't 12 volts to the alternator it won't excite and therefore will not charge. The black wire with the white stripe on the back of the alternator is the excite wire if this is a legacy outback.
Apr 2, 2010 at 10:42 AM
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NICK MAPLE
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ok, The standard rotor that spins inside an alternator contains an electro-magnet, which when energized creates a magnetic field inside the alternator creating AC energy. If that is correct, Would the power at start up that energize the rotor to create a magnetic field would it be from the 12 volt battery?

Thanks in Advance,
Nick Maple
Apr 2, 2010 at 12:57 PM
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RACEFAN966
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The power to energize the alternator comes from the black wire with the white stripe at the back of the alternator.
Apr 3, 2010 at 9:03 AM