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Voltage Regulator

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Old Apr 8, 2019 | 10:12 AM
  #1  
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Voltage Regulator

Does a 1999 F-250 Superduty 6.8liter have an external voltage regulator? I have the headlight/dashlight pulse at an idle.
Thanks Everyone!
 
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Old Apr 8, 2019 | 11:14 AM
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Ford has been internal regulator for many years now even before 1999
 
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Old Apr 8, 2019 | 11:19 AM
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Don't rule out the battery. If it is weak then you will get the pulse. A current (not voltage) output test will determine if the alternator is functioning properly.
 
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Old Apr 8, 2019 | 11:25 AM
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autozone calls out an Internal voltage regulator..

poor ground... at battery to engine or engine to frame
problems with a cell in the battery
even oil on the drive belt.. loose pulley on alternator ...

bad diode rack inside alternator ( 1 or 2 diodes are open..)... remove alternator and have it load tested at any good auto parts store..

even one of the 3 fields have issues..
 
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Old Apr 9, 2019 | 06:50 AM
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I noticed last night when checking voltage at the battery and at the stud on the alternator, that the voltage was doing the exact same thing at both locations.
When the truck is running, voltage is going from 14.7 to 14.8. to 14.9 to 15.0 to 15.1. to 15.2 to 15.3 really quickly and then starts over again.
Any thoughts?
 
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Old Apr 9, 2019 | 07:01 AM
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I take it you can NOT read my post..?????
 
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Old Apr 9, 2019 | 07:09 AM
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I did read your post. to speak to that...
I was able to find a listing of the ground locations so I spent Sunday afternoon before I posted on here, undoing every ground, cleaning, dielectric greasing, and replacing one ground strap from body to frame that looked iffy. Even added another ground strap ( since I had an extra) from the engine to the frame. I feel safe to say it is not a ground issue.

I pulled the alternator off after testing the lights again, and taking it to a shop here in town that builds alternators and starters. (Not going to the big box stores)

Battery is new, belt is new, and tensioner is working great.

Are you thinking alternator issue Chuck? I was reading a forum somewhere that possibly the headlight switch....
 
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Old Apr 9, 2019 | 09:08 AM
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Alternator Tested perfect. Guy at the Alternator place believes I have a bad "A terminal" wire going to the voltage regulator.
He gave me advice how to test and repair. I'll post back after complete
 
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Old Apr 9, 2019 | 02:15 PM
  #9  
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From: very South Texas
that would be the next step.. I would make..

Thanks for the update an tests done..

fyi.. just because the Battery is New... does not make it a good battery.... 100 amp load test....
5 percent of new batteries go bad the first month... 85 percent that make 12 months.. make 5 years....

many years under hoods....
 
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