Battery light comes on

1992 FORD EXPLORER
110,000 MILES • 4.0L • 6 CYL • 4WD • AUTOMATIC
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VENDCYCLE
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The battery light comes on when engine reaches about 2,000 rpm. The alternator is about four months old. I had it checked for replacement and it is fine. I replaced the voltage regulator and brushes and still the same result.
The voltage drops down to battery level at high rpm's and goes back to 13-14 volts at idle.
Feb 9, 2019 at 5:45 PM
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JACOBANDNICKOLAS
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Welcome to 2CarPros.

Was the alternator replaced or just the internal components? Honestly, there isn't anything on the vehicle that can cause this other than the alternator.

Internally is a stator is a stationary component which produces an AC current. Now, on your alternator, the stator produces current to terminals B and S. A predetermined voltage at terminal S operates the electronic control to open indicator switch, which removes ground from alternator warning indicator.

With that being said, I feel the problem is the stator. If it loses power to the S terminal, the indicator switch will kick on and most likely cause the alternator to stop working.

Let me know if that makes sense and if you replaced the entire alternator.

Joe
Feb 9, 2019 at 6:21 PM
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VENDCYCLE
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Got a another alternator from a locally owned rebuild shop here in town and it works fine. So I am out of the cost from the first alternator. I am going to see if they will refund my money back.

Joe, Thanks for the help...
Feb 15, 2019 at 7:07 PM
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JACOBANDNICKOLAS
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Welcome back:

I had a feeling that was the problem. Absolutely, I would return it.

Regardless, I'm glad you got it fixed.

Take care and let us know if you have questions in the future.

Joe
Feb 15, 2019 at 7:40 PM