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Losing battery voltage??

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Old Apr 6, 2006 | 06:40 AM
  #1  
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Default Losing battery voltage??

Hey guys,

what exactly does it mean when the battery voltage is boring the lower end of the redline, but the car cranks and runs fine on it? Also, all the accessories run good too...? Maybe because it rained last night?
Old Apr 6, 2006 | 06:49 AM
  #2  
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Default RE: Losing battery voltage??

When you step on the accellerator does it go up to normal? about 14v?
Old Apr 6, 2006 | 06:50 AM
  #3  
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Default RE: Losing battery voltage??

nope, it stays constant...

One time, the red batter symbol came up too. But it went away when i restarted the car after a whiile?
Old Apr 6, 2006 | 06:54 AM
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Default RE: Losing battery voltage??

Sounds like you car isn't charging, probably need an alternator
Old Apr 6, 2006 | 08:30 AM
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Default RE: Losing battery voltage??

ORIGINAL: Liquid_02

Sounds like you car isn't charging, probably need an alternator
+1 Have the system tested!
Old Apr 6, 2006 | 11:11 AM
  #6  
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Default RE: Losing battery voltage??

If you have a DC voltage meter, check it with an independent meter (voltage across the battery terminals with the engine runnong). Should go up to around 14, 14½ volts when running. If it's not charging, check your fuses. A blown fuse to the field energizing circuit will prevent charging.

All that said, LiquidO2 is probably right and the alternator is probably shot. You can take it off and most parts stores will test it on a test stand for you.
Old Apr 6, 2006 | 06:59 PM
  #7  
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Default RE: Losing battery voltage??

Id say its the alternator too, a car i had the voltage dropped to about 12v one day on my meter i took it to autozone or advanced auto parts they tested it said i lost a diode= new alternator [:'(]
Old Apr 6, 2006 | 08:03 PM
  #8  
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Default RE: Losing battery voltage??

get a new alternator before its too late. your engine will only run off the battery for about a day! i learned that the hard way.
Old Apr 6, 2006 | 10:01 PM
  #9  
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Default RE: Losing battery voltage??

Last month had the same thing happen to my ford work van,it was a sort in the colum shifter.Make sure its not your + or - posts,easy fix ,happened to me on a couple of cars,dont just replace parts,have alternater tested.Its usually not that.Let us kbow the outcome.
Old Apr 6, 2006 | 10:22 PM
  #10  
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ZachW04Stang
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Default RE: Losing battery voltage??

Hes basing it off the factory guage. It could just be the gauge is faulty. Normally you won't even notice a difference when the altenator goes bad on the stock guage. I would get a voltmeter and test the battery. With the car running it should be at 14 volts.



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