Charging system

2002 FORD F-250
300,000 MILES • 5.4L • V8 • 4WD • AUTOMATIC
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HARD CHARGER
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I had the alternator tested and it failed all the tests at O'Reily Auto parts. So I replaced the alternator and the drive belt because that too was worn out. The alternator drained a battery that I had bought new six months ago. So I replaced it too. When I replaced the alternator and drive belt the voltage seems to fluctuate more than the Chilton manual says it should. So is there a separate voltage regulator on my truck and where is it?
May 11, 2018 at 7:12 PM
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CARADIODOC
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The voltage regulator is built into the generator. You will need to provide me with specific test numbers to know where to start. Specifically, measure the battery voltage while the engine is running. If that seems to bounce around, also measure the voltage on the large output wire on the back of the generator and see if it is doing the same thing.

This article might also be of some help:

https://www.2carpros.com/articles/how-to-check-a-car-alternator
May 11, 2018 at 7:24 PM
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