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Discussion Starter #1
Hey guys, I got a 95 Bronco with the 351, and of course in michigan its cold. Well one morning on my way to school i had my rear defrost on and i came to a stoplight, and my voltage guage would drop down to the O on NORMAL. Then back up when i would take off, next light the same thing. Didnt seam like the lights would dim but it was kinda to light out to tell. When i turned the rear defrost off it would be ok when i would stop. So i was thinking maby my my Alternator is going bad. I checked the voltage of the battery while the truck was running and it was at 14.6V, is that normal? Seams like the last vehicle i checked was around the 15 Volt range while running. Hopefully you guys can help me out. Thanks
 

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CheeseBurger Milkshake!!
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14.6 sounds about right. If your concerned about it, install a real volt meter.
 

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Zombie Hunter
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Defrost is is a huge load draw, that's normal.

The 3g will eliminate the fluctuation, but you're not really operating outside the norm
 

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:stupid

Your battery's full charged voltage is only 12.6v, 13.6-14.4 is normal charging voltage. Anything higher then that really, and you're into battery cooking territory.

My voltage drops a bit when you put the rear defroster on, a pair of 100w headlights, other lights, the blower fan on max, and the stereo turned up. It's just loading up on the alternator, and then starting to drain down on the battery... totally normal.
 

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Discussion Starter #7
Ok Good, Yea ive done some info bout the 3G. I really want that now lol. Thanks guys for your help.
 

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Sounds normal, mine does the same thing. Gotta upgrade that 95A alternator to something a little beefier.

Ive got a 160A alt. waiting to go in. Just gotta figure out that damn charge cable.
 

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After installing a new 3G 130A alternator, i noticed that my dash gauge would run at 13v dropping to 12v with accessories on. :doh0715:

I then tested it with a meter under the hood and found the battery to be a steady 12.6v standing, 14.4v at engine idle and no change 14.4v with all accessories on. :hump

Funny how the dash gauge shows a 13v to 12v drop with accessories - must be the resistance gremlins to the OEM gauge itself... :shocked

Not a big problem, just annoyingly inconsistant. I would think that the OEM dash gauge should stay steady at 14.4v when running? How to fix? Rewire the dash OEM gauge to remove any resistance? :scratchhe
 

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Bigger supply to the dash is the only way to solve that... but IMO, "NORMAL" isn't a very informative volt meter. :rofl:

Just stick an aftermarket somewhere on there and call it good.
 

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Zombie Hunter
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After installing a new 3G 130A alternator, i noticed that my dash gauge would run at 13v dropping to 12v with accessories on. :doh0715:

I then tested it with a meter under the hood and found the battery to be a steady 12.6v standing, 14.4v at engine idle and no change 14.4v with all accessories on. :hump

Funny how the dash gauge shows a 13v to 12v drop with accessories - must be the resistance gremlins to the OEM gauge itself... :shocked

Not a big problem, just annoyingly inconsistant. I would think that the OEM dash gauge should stay steady at 14.4v when running? How to fix? Rewire the dash OEM gauge to remove any resistance? :scratchhe
i don't trust any factory gauges. Sometimes i think they are just there to fill space so the dash isn't empty, they are the farthest from accurate.

I have aftermarket gauges mounted for everything, oil pressure, and voltage being the two big ones, if my dash gauges start doing something stupid i just look over at the mechanical aftermarket gauges to make sure everything is okay.
 

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crank trigger
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i don't trust any factory gauges. Sometimes i think they are just there to fill space so the dash isn't empty, they are the farthest from accurate.

I have aftermarket gauges mounted for everything, oil pressure, and voltage being the two big ones, if my dash gauges start doing something stupid i just look over at the mechanical aftermarket gauges to make sure everything is okay.

do they deviate much from one another?
 

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do they deviate much from one another?
You're talking about the stock gauges deviating from the mechanical ones right?

If so... um, they can't deviate if the stock gauges aren't actually feeding you quantitative information. You can't compare (L NORMAL H) to (8v 10v 12v 14v 16v 18v).
 

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My dash OEM voltage gauge shows volts, not "Normal". Again, it drops from 13v to 12v when accessories are turned on, as opposed to a consistant 14.4v shown by multi-meter under the hood. The OEM gauge is inconsistant with an accurate meter under the hood.

Would it help to install a larger power supply wire to the dash which might provide less resistance? Otherwise, I could replace one of my A-pillar pod gauges to voltage.
 
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