Electrical system

1999 FORD MUSTANG
1,000,007 MILES • 4.6L • V8 • 2WD • MANUAL
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242MUSTANG
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GT model. replaced battery and alternator now charging gauge on dash intermittent. some days system charges other days the gauge starts dropping. it is crazy.

I have been replacing and rebuild alternator in the car too many times.
Apr 30, 2018 at 10:17 AM
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ASEMASTER6371
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Good afternoon.

The first thing I would do is to use a voltmeter at the battery to confirm the voltage.

the dash gauge is not an accurate gauge to follow.

can you check the voltage at the battery?
Roy
Apr 30, 2018 at 11:36 AM
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242MUSTANG
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I will check this ASAP.
Apr 30, 2018 at 12:05 PM
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ASEMASTER6371
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Okay, will be here.

Roy
Apr 30, 2018 at 12:06 PM
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242MUSTANG
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Thanks.
Apr 30, 2018 at 12:29 PM
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ASEMASTER6371
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You are welcome. Please keep us updated.
May 2, 2018 at 4:28 AM
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242MUSTANG
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Battery voltage reads good 12+.
May 2, 2018 at 5:34 AM
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ASEMASTER6371
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Okay.

Exact voltage? 12 is a dead battery. 12.6 is fully charged.

Is this with the engine running or engine off?

Roy
May 2, 2018 at 5:36 AM
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242MUSTANG
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Off.
May 2, 2018 at 7:01 AM
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242MUSTANG
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13.9 running.
May 2, 2018 at 7:01 AM
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ASEMASTER6371
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Should be 14 to 14.5.

Clean the battery cables and retest. If it is still that low, replace the alternator.

Roy
May 2, 2018 at 7:21 AM
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242MUSTANG
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Cool.
May 2, 2018 at 8:30 AM
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ASEMASTER6371
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Keep us updated on your results.

Roy
May 2, 2018 at 10:03 AM
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242MUSTANG
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I replaced the alternator so far my problem is resolved.
May 8, 2018 at 9:18 AM
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ASEMASTER6371
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Good, glad to hear it.

Good job!

Roy
May 8, 2018 at 10:17 AM