1999 Ford Aerostar Alternator Light Comes On You Turn Fan Switch On Matter Seed

1999 FORD AEROSTAR
120,000 MILES
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Alternator light comes on when you turn the fan switch on, no matter the seed of the fan ,motor blows air no wierd noise?
Dec 3, 2012 at 11:51 PM
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CARADIODOC
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Most likely there's one defective diode inside the generator. That will reduce its maximum output to exactly one third of its rating, and that's not enough to run the entire electrical system. Have the system professionally load-tested. If one of the six diodes is bad, "ripple" will also be very high.
Dec 4, 2012 at 1:15 AM
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