Figured out how to keep steady voltage

Discussion in 'Audio & Electronics' started by NathanJax, Feb 21, 2014.

  1. Kenny D

    Kenny D Full Access Member

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    I was talking about this mod with him and he said, lets try it. He killed his truck and we unplugged it. He cranked it up and it was around 14, his digital meter was reading 13.7 and then after about 3 or 4 minutes, it dropped to 12.6 and it stayed there for a while. There was basically no change when he revved up. It did return to 13.7 but it would still fluctuate at idle. I haven't had the chance to speak with him to see how it is now or if he plugged it back in, but I will update once I speak with him.
     
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  2. denalianyone

    denalianyone NYBlackLade08

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    Glad I found this sticky before dropping some coins on a new alternator. Now my readings range from 14.3-14.9 constantly even with headlights and radio on. Thx to idatalink with my nex4300, I can see the precise numbers while driving.


    Sent from my iPhone using Tapatalk
     
  3. Nosho47

    Nosho47 Full Access Member

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    How does this work with aftermarket alternator? When i startup my tahoe with my stock alternator, voltage starts up at 15.7 and gradually goes down to 13.2v. With my 370 amp alternator, it starts up at 16.3 and goes up to 16.8 and then goes down when i put it un gear. The problem with that is amp amplifier goes into protect because of the voltage being to high. Will removing that one connector help?
     
  4. puckhead

    puckhead Full Access Member

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    I will be doing this tonight. They try to over complicate things and make it difficult for those of us who want to keep these a while.
     
  5. 09_4WD_YUKON

    09_4WD_YUKON Member

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    Lights still flicker after doing this. Will be adding Big 3 wiring to it soon to see if that helps.
     
  6. mikeyss

    mikeyss Full Access Member

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    I had mine unplugged before and didn't really notice a change. I have dual batteries and the only weird thing I notice is in the morning when I start it and let it run, the interior lights have a very slight flicker. It does this regardless of that thing being plugged in or not. So I just leave it plugged in these days.
     
  7. swathdiver

    swathdiver Full Access Member

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    My views on this item has changed as I now understand that it is more for extending the life of the battery and alternator and not solely for fuel efficiency.

    There are detailed explanations on how this system works in the shop manual and the GM Upfitter's manuals. Look up the key words EPM (Electric Power Management) and RVC (Regulated Voltage Control).

    For those of you with radio controlled cars, planes, boats, etc. this is basically a smart charger built into your truck, pretty cool.
     
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  8. 09_4WD_YUKON

    09_4WD_YUKON Member

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    Found this on another site..."Voltmeter Fluctuation Condition:
    Some customers may comment that the voltmeter is fluctuating between 12 and 14 volts on their full size pickup or utility vehicle. Starting with the 2005 model year, light duty full size pickups and utilities are equipped with a new Regulated Voltage Control (RVC) system. This system reduces the targeted output of the generator to 12.6-13.1 volts when in "Fuel Economy Mode" to improve fuel economy. The generator may exit "Fuel Economy Mode" if additional voltage is required. This will cause the voltmeter to fluctuate between 12 and 14 volts as opposed to non-regulated systems that usually maintain a more consistent reading of 14 volts. This fluctuation with the RVC system is normal system operation and NO repairs should be attempted."

    The only thing with mine is that when the voltage drops, the headlights dim significantly. Is this part of the AFM? If so, would turning it off with a tune possibly fix it? What about upgrading to the 160A alternator? Mine has the 145A now.
     
  9. Galante

    Galante Elite Member Supporting Member

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    Afm is related to lifters and has absolutely nothing to do with electrical system. Yes a 160amp alt will help but check yer battery first. Have it load tested.
     
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  10. swathdiver

    swathdiver Full Access Member

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    Not part of AFM. It's controlled by the BCM. On the negative cable right next to the battery is the RVC sensor with a 3-wire plug. If you disconnect it, the alternator will produce full power and I do not think any codes will set.
     
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