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What does your battery voltage sit at?

Based

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#1
My battery voltage is weird. Sometimes it'll sit at 12.6, sometimes it'll jump to 14.5 when I get on the gas, and then when I decellearate it'll go to 13.5 or just some lower voltage. Sometimes it sits at 14.4 when I'm idling, other times it'll sit at 12.6.

So can you guys/gals monitor your battery voltage for me please? The way I'm monitoring it while driving is my Accessport, but when i have checked it with my digital multimeter while idling and the Accessport says 12.6 and it indeed was 12.6.

I am concerned with this because I plan on upgrading my sound system. I need it to be at 14.4 all the time to get consistent power from my amp(s). Right now I have a 1200 watt amp wired at 2 ohms so it's pushing out around 800 watts. The battery voltage does not go down upon bass hits so I know the alternator is keeping up with it, it's just weird that my voltage just randomly goes wherever it wants.
 


OP
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Based

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Thread Starter #2
This is what I just now got:

Car off - 12.43v
Car cold start - jump to 14.9v, then gradually drop to 13.0v, then rise to 13.2v
Rises as car warms up
Stops at 14.56

Now that is just on first idle. It will fluctuate as I drive.

And I compared what my DMM said compared to my AP and they were 0.05 volts apart or so.
 


Sekred

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#4
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Based

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Thread Starter #5
As long as the charge light is off and there are no CEL codes then your system is probably operating as it should. I think most current Fords use what is called a "Smart Charge" system so battery voltage can vary 2-3 volts or so during operation, see link.

http://www.hella.com/startersaltern...i_en_electronics_ford_smart_charge_system.pdf
Man that's annoying. Just one more thing I need to bypass.



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fairbanks
#6
The Car will turn off the alternator when battery full and not using high demand so I've read in Taurus forum for better fuel econ it will even wait to see a constant speed i think before charging if its not that dead.

You can try testing it if you have something to drain battery when running like a amplifier maybe stock system on full and blower on full?
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CanadianGuy

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#7
The Car will turn off the alternator when battery full and not using high demand so I've read in Taurus forum for better fuel econ it will even wait to see a constant speed i think before charging if its not that dead.

You can try testing it if you have something to drain battery when running like a amplifier maybe stock system on full and blower on full?
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I can confirm that. The alternator like the AC compressor are on as needed basis to help fuel econo.
 


Capri to ST

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#8
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Based

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Thread Starter #9
I can confirm that. The alternator like the AC compressor are on as needed basis to help fuel econo.
Wow that is interesting. But I hope I can bypass that somehow.


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OP
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Based

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Thread Starter #10
Ok so I've been reading more and I now understand what is going on. Exactly what you guys said. It's just a smart charge system that is controlled by the PCM.

I wonder if I can just unplug the PCM connector at the alternator.


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